They get the job done.
Downside; You'll notice a slight difference in the horsepower between different batteries and sometimes a variation in flight times.
Upside; I bought a number of them back in the last half of 2010 and to their credit all of them are still working except one which was my fault (drew too many amps for it).
As long as you don't push them (upsize them a little to keep under their max amps) and give them an easy charge (don't exceed 1.8A for a 2200mAh battery for example) they will do fine.
So if you are the kind of guy that spends your entire life on full throttle stick, high timing on your ESC and fast charges at the field then they probably aren't the batteries for you and cheaper will be more expensive in the long run. You'll cook anything that's not quite up to scratch in no time.
If you are a bit of a lazy flyer, spend most of the time at 1/2 to 3/4 throttle, use Auto ESC timing and don't mind extra charging time at home? They can do the job for you.
To be perfectly honest I wouldn't buy them again. False economy aside (because you can make them last if you look after them), the better consistency and faster charging times on offer from another cheap brand like Turnigy or Zippy just make the extra few bucks well worth it.
The turnigy is only about 3 bucks more per (2200mAh 3s 30C). The Zippy is considerably more ($8) but IMO is the best of the 3 batteries in terms of performance (and also the lightest).