The rollers on Loch Lomond can be a bit moody, but you learn to live with them
If it's quiet enough on the loch (i.e. early/late in the day) then they're not too much of a problem.
You can ride pretty much anywhere on the loch as long as you are 150 metres offshore and not inbetween the islands. Best get yourself one of the booklets outlining the areas you can/can't board in, as well as listing all the byelawas, from the centre at the public slipway (Loch Lomond Shores at Balloch). We got stopped just yesterday for boarding too close too shore. My bad as I hadn't read the booklet and thought it was 100 feet. Oops. (apparently if you get stopped three times for breaking the byelaws you can get prosecuted - fair enough really!)
I ride behind a rather crappy 15ft Picton with a 60HP Yamaha outboard. Engine is powerful enough to get you out of the water, but the wake sucks big time. I'm still learning though and I guess it helps me practice my surface skills. Think the biggest air I've had behind that boat is about 2 feet ....
ops:
Simon