Joey,
Was just talking about this earlier. I have 20 and 30cc planes as well. When the 20's first came out I was running 50:1 in my 30's, and switched them to 32:1 for the simplicity of maintaining one mixture that works well in everything - like you are considering. Well, now that I've been running the 10's as much as I have been, I've switched everything to 20:1. There have been NO notable downsides to doing this to date (end of first season). I did have the exhaust off an RCGF 20 the other day as I was curious what the ring groove looked like. I've been hammering on it all season, so I was half expecting to see it loaded up with carbon. Happy to report there was no problem at all. I'm sure this is a result of running a quality oil.

It should be noted that with the tiny amounts of fuel these little guys are using (10-20cc engines), if you do not increase the oil content in the fuel flowing through the bottom ends, you run a much higher potential of smoking an already highly stressed bottom end....

It's not like running more oil is costing you much in the way of performance. It's not like you're going to be able to jump to the next larger prop size by switching to a leaner oil ratio. The ONLY down side I've noticed is cost. I'm now going through twice as much oil as what I used to. From where I'm sitting, that's a small price to pay for being able to fly these 10-20cc gassers again. They're so much friendlier when it comes to handling/care/feeding, the 30cc stuff is now getting dusty... -Al