the third accessory is the alternator. i don't recall if there were any issues with the JDM one, can't imagine there would be, but i just switched all three while i was at it. but it is worth mentioning that some people run the JDM AC compressor because it's lighter. i guess they get the lines that connect directly to it, and figure out the connectivity of the condenser side of them.
i'm running 346 lb/ft through the stock STi clutch, as per Airboy road dyno software. it's been holding for about 15K so far with no issues.