Hi, and welcome to this edition of... My 2 Lumens. There will be plenty of more detailed and technically qualified reviews out there so this is only intended to be a super quick overview to temper my giddyness with a new light purchase 
Just remember these are my opinions and are subjective. The idea is to cut through the glossy photos and brochures to give you a simple laymans overview -- perhaps draw out some discussion.
If you want more technical details like "is it PWM, how many amps does it draw... etc" please see Selfbuilt or other long standing member reviews (coming). Sometimes I'll put the mA draw information on different modes if I want to know (or are asked).
Model: Jetbeam RRT-01
Battery: XTAR 16340 600mAH
Rated Lumens: 500 (20min, RCR123A), 220 (1h30min, CR123A) 0.005 (100hr, CR123A)
SOS / Strobe: "Hidden" SOS
Multi Mode: Infinitely variable
Reflector: Smooth "two-section curved reflector"
Beam: Bright spot with wide spill. Multiple rings with visible purple fringing.
Finish: Slightly textured "charcoal" black HA III aluminum
Notable Features:
- comes with screwed Ti clip
- SS bezel
- different lanyard, black with logo (as opposed to dark green one)
- pleasant tint, ever so slightly more green/neutral than several SWM V10A/R T6 compared
- small size
- nice deeper knurling (as compared to RRT-0)
- twist ring has shorter travel than RRT-0 but slightly longer than V10R
- deep knurled twist ring can be activated with one hand
- noticable detents at standby and turbo
- wider spill than V10A/R T6 and RRT-0 XML SMO
Quirks:
- does not tail stand well due to slightly protruding lanyard button
- will not tail stand (straight) well at all if the lanyard is attached
- "ringy" smooth reflector may be the contributor to the very ringy beam pattern. Might also contribute to the purple fringing at the edges.
- IVR ring has up/downward play
- IVR ring has a gritty feel when twisting
I Like it Because: It's small, barely bigger than the Ti clip itself. A good 4mm smaller than the V10R T6. Charcoal color and slight texture is nice.
I Dislike it Because: To be honest if it didn't have the Ti clip or the SS bezel, I would give it low marks for execution. Somehow it just feels "toyish".
Additional Comments: In my pictures you can see I do have a few other comparable lights (not all shown). Somehow I feel it's only a minor step up from the Quark 123 (pictured). I can't put my finger on it but my gut feel is it doesn't deserve the asking price.
Other Technical Reviews: None yet. Let me know and I'll add it here.
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Current Draw:
Meter: Sigmatron SDM-58A
Battery: XTAR 16340 600mAH
Low: TBD
Turbo: TBD
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Please excuse the iPhone pictures!
Nice pics .
Nice quick review and very nice pics.
for those of your interested, we're trying to put together dinodirect groupbuy here:
http://www.thebrightsideforums.com/viewtopic.php?f=21&t=1488&start=20#p23109
Nice light, but a little to rich for the old man.. 
Dinodirect has a coupon code to reduce this to $79.99 at the moment; 'RRT01' at the checkout.
If your chasing the lowest mode, this is theeeee light to get. Crazy low low awesomeness, great review Ualnosaj
Kind of risky buying such an expensive light from DD?
I don’t think it’s that risky. They always seem to deliver the goods, eventually.
If there are QC issues with the light of course you will then have to probably go straight to Jetbeam as the after sales support is not so good. But with such a high quality light you’d hope the QC would be good enough for you not to have any issues.
It is a wicked price, but, alas, it s no more. Price back to $95.
If you’re chasing a wicked low… the TC-R1 is the fellow to get. It goes so low I swear it’s just an afterimage in my eyes! The TC-R1 has definitely had the most “pocket time” in the past few months. If I can get the TC-R1 in a warmer emitter then it would be perfect (maybe modding soon).
Granted, the RRT-01 is a better $$ value. If you go there, the EYE10 is an even better value for what is pretty much the same light!
Very well done. Thank you.