Battery packs, build or buy?

[Spr0k3t]

I'm looking to get the most consistent power from a single set of 7.2V stick packs. So I start researching and have found many different methods of doing just that. One thing that is recommended is to use a warming tray in the pits to keep the power consistent. Another method is charging/discharging methods.

So I'd like to know some recommendation of brands. Should I build my own stick packs or just go pre-made? Is there a benefit for building if I only need the standard stick pack?

Keep in mind, I'm not looking for max power... that's what my 11.1v 3s LiPo is for.