That is such a good idea John. :clap:
Like you, I got fed up with wrecking planes so I got myself a combat wing and never looked back. If I crashed it into the ground I could just pick it up and launch it back into the air

, instead of coming home with a bag of kindling!
(They’re also great fun to fly combat with other pilots. Although hitting other planes in flight is a lot harder than you might think! :!: )
How long your battery lasts will depend on how aggressively you fly. Just floating around with gentle turns should give you half hour okay.
If it’s of any interest to you, what I used to do for my own interest was to fly for ten minutes. Land and recharge the battery, noting how many mA the ten minute flight had used.
K
p.s. Does your UBEC have a Low Voltage Cut off? (LVC)