Skip just stick with lipos, its getting cheaper and cheaper and cheaper. Here is what you want to try as a baseline for the plane, brands suggested are something for you to use as referrence:


For 4S, you will have nice power for aerobatics

Motor - AXI 2826/12, DualSky 4260-5
ESC - 60A like Turnigy or Dualsky
Batt - 4S 3,700 t 4,900 mAh 25C, you may need the weight
Prop - 13x8 to 14x7

5S, you are talking about from superb performance to unlimited verticals

Motor - DualSky 4260-5 (hot setup with 12x8 or nuts with 12x10) or DualSky 4260-6, Plettenberg Orbit 25/18, AXI 4120
ESC - 80A like Turnigy or Dualsky
Batt - 5S 3,700 t 4,900 mAh 25C, you may need the weight
Prop - 13x8 to 14x7

Caveat - bipes are a pain in the butt when it comes to EP unless you can fashion out a hatch for access.