1. Yes I'm very pleased with my OS.91 pumped motor and 15x4w prop. It's quite overpowered but balances straight out with this motor. Because of the power you need to run the motor in carefylly and get it to idle well before flying ( 3-4 tankfuls) and be very careful with the throttle. I never (almost) go above 1/2 throttle except in uplegs and pulling out of hovering and tight spots. You can rip the machine apart if not careful.
Bill Ryan has a review on hiw with a Saito .91 on "Behind the flightline" www.pitsbros.com.

2. Yes I believe so. I have only done it inadvertently, not on purpose
3. Yes, not bad but there is. See Bill Ryan's writings in the above forum and previously on this thread

Further: its standard to break off the landing gear on this machine, you need to do it in order to get some epoxy and pins into the LG block. I did in the 4th flight by harrier landing it in rather tall grass.

Have fun

Björn