I do similar to RCIGN1. I run only 3 of the 6 bolts on my DA-100 in the air. The bolts weigh 1/3 of an ounce each, going from 6 to
3 saves an ounce!

Backfires will kill anything. Often, the first backfire loosens the prop nut or compresses the wood, making way for the second to destroy things. Always tighten everything up after a backfire then fix the problem that caused the backfire before starting again.