Let’s compile a list. I’m speaking of single die type emitters, not COB. If you have a source for the LED you mention feel free to leave a link as well.
I will start… I’ve created a google sheet that I’m adding to. I would love to have a few volunteers to help EDIT the sheet. If you want to have edit privilege’s PM me your email and I will add you as an editor.
There’s also:
W5050SQ3
And the FFL505A
These are the only ones I know of, including some in the spreadsheet.
The FFL505A is a funny one. It has a round light-emitting surface, but technically a square die. It only appears round because the corners of the square were covered with opaque silicone mask, which is part of the reason for its low efficacy.
EDIT: it actually has a round die, the FFL350RD is the square one. Thanks crbnfbr and koef3 for the correction!
Excellent, I have added both W5050SQ3, and the FFL505A. I’ve also included a line on the spreadsheet that links to independant tests of the LEDs. I found some here at BLF done by koef3LED tester
Thanks for the input guys.
I thought it was only the FFL350RD that had the square die and silicone mask. I thought koef3 had confirmed the FFL505A was an actual round die.
edit: Yeah, FFL505A does have an actual round die.
Only the FFL350RD has round die masking. The FFL505A has a real round die chip.
Thank you for the corrections, I have revised my original comment accordingly.
Oh.
I got confused for a second.
Cree has announced the release of the XP-LR and XP-GR. This gives me hope that there will be more competition in the round die LED space. If cree can make any advancement in color blending, efficiency, CRI they have my full support 
So far the best small round LED I have found that I can get in warm tints is still the LMP W5050SQ3. The 3000k version has good blending and respectable output, but surprisingly low CRI (only 70)
koef3 has already started a thread here breaking down the characteristics of the LED.
XP-LR Datasheet: https://downloads.cree-led.com/files/ds/x/XLamp-XPLR.pdf
XP-GR Datasheet https://downloads.cree-led.com/files/ds/x/XLamp-XPGR.pdf
were there any new round die leds recently?
I’m not sure there’s a better place to ask, but what is the difference between the YinDing “egg” round die, the FFL505A round die, and the w5050SQ3?
I’ve read that the w5050sq3 runs much cooler. I was going to buy a 3000k version from Jackson. I have the 1st gen rosy ffl5050 round die in 3700k (which is quite underwhelming), and bought a 6500k high CRI one to test out.
I had a YinDing “round die” in 3000k, but accidentally lifted the entire white silicone(?) part off the top of the emitter and the die was a weird square shape underneath.
I will eventually get all three to test out. on reddit people are saying the w5050sq3 6500k is great and very cool running. I’m not sure where to find the high CCT version except maybe KaiDomain.
basically, I’m just asking if there are any glaring big differences between the three, exceptong tint and CCT. I’ve kinda been researching them but couldn’t find emitter tests for some
also, I’m kinda excited to receive my FFL707MD. the specs state 6V 12A rating, 4200k, 96 CRI, very slightly negative DUV (-0.002). it looks like a quad ¼ circle die. there is also a 5050 emitter that looks similar that I think is 3V.
I believe it’s technically a round die emitter, although there are what looks like bond wires on each “corner.” hopefully the corners are not part of the die/phosphor to avoid sideways light leakage. I haven’t seen anything about this emitter yet. I assume the die is of similar size to the SFT-70?
I might put it into my L21A, and take its XHP70.3 HI 4000K R70 out and into a TS22 or KR1. I could test out SMO vs OP reflector in that light.
Thank you for linking your review. I never saw it under a different name (like most FFL emitters).
I’ll have to double check if the one o got was 3V/6V. not sure which light to put it into now. considering the slightly disappointing output. would I be correct in assuming that a 8A driver would be fine?
just checked, it’s the 6V version. he lists it rated at 12A. I have a 6V8A convoy driver, but that’s 8A@6V and I feel dumb but I can’t remember the conversation ratio once you bump the voltage up.
I usually try not to buy from this store for various reasons, price being one of them, but I do understand somewhat as living in a remote place will increase all prices. I’m not sure why it’s listed at 12A, but I’m glad you linked your review.
Since the driver is rated at 8A @ 6v there’s no conversion required.
I think you’re thinking about Watts.
I cannot say for sure that my LED tested is the same as for FFL707MD (or whatever it is called by FFL). There was no official confirmation from anyone, this is just based on the design of this emitter.
I swapped the XHP70.3 hi in my M21A out for the 707MD. it has the black convoy 6V8A driver. I have a purple 6V8A (8.25A) driver in another light, not sure if the black one is an older version or what.
So far, it seems to be quite nice. good tint, with no real green. OP reflector (10mm?). my SMO reflector for this light seems to have a slightly smaller hole, didn’t fit. nice hotspot with the OP though.
I ran it on 100% for a while, and seemed to run quite cool. after 30sec it was still just warm. this LED is pretty nice I think. I haven’t taken any pictures yet, and the CRI and R9 looks good to me. I’m happy with the purchase, and am considering getting another.
There is also the L50.
Don’t know any more about it, but just put one in a Convoy M1 with a 10A driver. 70 CRI, DUV on BBl, 2000 Lumen @10A.
Seems like a budget version of the SFT42R/XM-MR and a good alternative to the sft40 on 8A.
If I ever order from KaiDomain again, I’ll probably grab one of those. They have a lot of parts that I need, but last time I had trouble with them. My shipment took over a month to leave China, cleared customs quickly, and then went to Texas and sat at some distribution center there for over two months.
I tried to get ahold of the carrier, tried to get ahold of KD, everything. after two weeks and a couple emails to KD they finally responded and it showed up on my porch within the next two days.
I almost don’t want to risk dealing with that again, but like I said, they have so many parts that I can’t really find in other places.
back on topic, that emitter looks quite like the 707MD, just smaller. Who knows if it’s the same manufacturer. I’m certain that the FFL351A and NTG35 are the same emitter made by the same mfg just to slightly different specs. same with FFL5009R/NTG50.
I did get this L50 before, in both 6500k and 3000k. the 3000k had very awful tint, but the 6500k wasn’t too bad, for 6500k. edit 2: I’m going to guess both L50s are the same, except the one you linked has silicone over the emitter whereas the one I showed is glass like the SBT90.2 for example. iirc it had magenta AR coating. I still have the 3000K one somewhere
I put it and a convoy driver into a little zoomie for my friend. made it much more powerful than stock. here is the light: edit: the one on the right that is laser engraved “PROBE SHINY”
It’s just a hair larger than a Convoy T3 in every dimension. The light really sucked before, but now it’s actually pretty decent, for what it is. sorry for writing an entire book, I always let it get away from me.
You show the 20W Version, which is rated at 5A max. I linked the 30W version, so 8A - had no problems running it on a 10A driver with a ampace JP30, so I would say it can be overdriven quite a bit.
Would be interesting to know if the die size is the same, the 30W is the same size as the SFT42R.
Edit: have ordered several times from Kai to Germany. Sometimes it takes a few days till shipping and shipping is slower than e.g. convoy, but everything arrived within 2-3 weeks. Would say you had a bit of bad luck.
