2 questions
1. I read there are different bins of these chips - if I order these, can they be stacked on any 7135 based driver w/o concern for bin of existing chips?
2. What is the max amperage - maybe 'recommended'...and 'theoretical'...
I have a big role of those if you want I will sell you some for 50 cents a piece and you won't have to wait an eternity to get them. Send me a PM if you want some.
1.I am not sure about stacking on the different binned ones I haven't tried yet, but theoretically they should work.
2. I have had trouble going over 3.5 amps mostly heat issues with the chips coming unsoldered because I am driving XMLs and heat becomes an issue over 3 amps. I have seen people successfully stack them high and run SST-90s with them.
1. Yes.
2. it's limited only by the connections/tracks (they must carry the high current), the batteries (which shouldn't drop the voltage too much under the high load) and thermal issues (those chips produce heat, too).
There's nothing wrong to power an SST90 with 9A using 26 AMC7135s on 3*18650 in parallel for example.
edit... ah, E1320 was faster...
AWESOME!
I already ordered from intl-outdoor, but only 15, and I'm sure i'll be wanting more, so eventually you'll get that pm.
we'll have to see how good I can get at actually connecting them - then I'll find out how well potting w/ devcon 2 ton and alumina manages that heat...
edit - thanks guys!
Craig @ IlluminationSupply.com has them for sale as well.
Rumor has it that he is carrying the 380mA-binned versions too. 
Weird... I've done dozens of mods with double stacked chips on sandwiches and never had any heat problems, but I don't run on afterburners except for grins.
In the Neutralizer mod, I used 3 boards with two extra chips to make each 3.5A, and run it on 4 NIMH C cells. I think the trick is to not run higher than ~4.5V for multi-emitter setups so not much voltage has to be sunk.
(Usual violin mantra: Ghetto level income so no lathe to conjure up heatsinks.) Really, if it wasn't for my wife's income, this whole freight train would come to a juddering, screeching, coupler-slamming halt.
Rich
Do you want to see the 26x 7135 on one board?
Here it is - Andi, the man who made it, is also active sometimes here on BLF.
Thanks man! I've been looking for that picture for hours, but couldn't remember where I've seen it! I need something like that for a PT-54 that's collecting dust on my desk ;)
so - how about the reverse - stripping chips
I want to make a 2.8A a 1.4A - does it matter which ones I desolder?
Also, I assume I'll have to jumper the traces after removing the chips?
doesn't matter which ones..I did the same thing and removed the 4 on the battery + side..worked great and showed 1.4a
Bloody hell, your posts just reminded me how much I really miss the good eyesight and steady hands I had 20 years ago!
The days of near-microscopic work are over almost, for me. 
thanks - what about reconnecting traces? I don't understand why there are 3 leads on one side of a chip and 1 on the other...
not necessary about reconnecting traces..just pull the chips and it's all good..
great thanks. two came off properly, but pulled the center trace off the other two 
centre trace as in the metal under the black chip part? get rid of it all..there doesn't need to be any connection at the 7135 chip as they are all in parallel..metal and black part need to go..heat gun with a fine nozzle works great..
oh, i pulled it all. that was by mistake, I was hoping to save them, but tossed those two in the trash...
next time I'll use a blade tip to touch all three connections at once.
ah ok..yeah they do come apart sometimes..sucks if you're trying to save them..I can never solder them on top of each other so i've stopped trying lol..
I just got those two installed on another board.
I haven't tested it, but it looks ok. I actually had a tougher time w/ the large single lead than I did with the little ones. the soldering iron e1320 recommended is f!$$%#@ awesome.
the aoyue one for 40$ off amazon?
yeah I don't know my soldering iron works it's just the solder doesn't go where I want it to..you tin the legs then put them on the apply heat to the legs? the legs don't seem long enough for me..
$35.10 ! ebay
http://www.ebay.com/itm/110661676275?ssPageName=STRK:MEWNX:IT&_trksid=p3984.m1497.l2649
I didn't tin them. I held the chip in place with my fingers and bent the legs down w/ a small punch, held the chip in place with a clip and soldered the outside connection then put a tiny bit of flux on each leg w/ a squeeze bottle/hypodermic needle, then soldered each one by putting the tip almost parallel w/ the leg and trying to touch the board and leg at the same time. The key part for me was getting just the right amount of solder on the tip.