I've been out for a long while, and am getting back into it now. But have been doing FPV quads and wings pretty hard. 1/10th scale I assume since you are building it around a 550 motor. "Best" lipo is likely going to kick off some form of Ford vs Chevy vs Dodge debate. In 1/10 buggy's and stadium trucks, I like 2 cell lipo hardcase batteries. The Zee brand 2C 5200 mAh packs look to be about $35 for a two pack on amazon. And I use these pretty hard. They are only 50C batteries. But I seriously doubt a brushed setup with a 60 amp ESC would strain them. Serious racers usually are running Protek, Orion (are they still around?), Maclan, or some of the other very expensive LiPo brands. Best???? I'm still a Max Amps fanboy, and will likely always be. Though I can't justify super high end packs for the basher I am going to try to jump someone's house with.

Gens Ace is good, as well, I'm sure I'm missing a bunch. Should mention CNHL lipos get run in my FPV quads and slammed into stationary objects at mach Jesus, So I'd happily run those in a traxxas that I'm launching from a skatepark.

Hope that helps.