I put some lube on the prop shaft part that goes inside the gear box and just a little on the gear and pinion. I forget exactly what name, but it's a very light liquid lube with teflon. It's as thin as water. My friend uses it on copy machine gears. I just did a quick search on the internet and there is "Finish Line Teflon-Plus Dry Lube" that you can find in bike shops. Anyway, it made the plane even more quiet and added a bit more power. The plastic bearings in the gearbox suck and they wear out after a while. Even if you haven't damaged or bent your prop shaft, that plastic bearing wears out and the space gets bigger making the the prop shaft vibrate more as it spins and you loose efficiency. Dirt and dust craps out the efficiency as well. Clean it out periodically.

All I did on my Slo-V was lube the prop shaft, use an 1180 prop, moved the clevis to the second to the innermost holes on the control horn. Using stock motor and battery (and Mode B, of course) I get a pretty good climb rate.

[link=http://users.cwnet.com/dhsc19/Slo_V_Aerobatics.wmv]Slo-V Video[/link]