Turnigy Nano-Tech batteries seem to work well in general. It does seem that their life span is a bit shorter on average than A-brand batteries, but some people stretch them to the limit that's on paper. If you charge them at 1C and don't run very near the discharge limit of the battery they should do very well
As for the brushless sets... watch out carefully which ones you're buying. For example I heard the HobbyKing TrackStar has a flawed throttle curve (it's like all or nothing).
The set I use form HobbyKing is the X-Car 100A ESC+6.5T (5200kV) motor. I heard some are having problems with an inconsistent brake, but apparently turning down the EPA on your transmitter to 90-95% in both throttle and brake direction does the trick. I have not had these problems, for me it has worked flawlessly so far
I received my second (exact same set) one week ago and I'll try that one soon too.
I have my fingers crossed everything keeps working well, as whatever I buy on the front of electronics (phones, laptops, ESCs, A-brand+high end product or the cheapest of stuff) I always seem to have problems. One of the few bug-free-ish electronics I've owned so far are my trusty 2005-ish Nokia 1101 (still in use today, though it's starting to show problems lately) and surprisingly, that HobbyKing ESC I just mentioned!
