As Jeremy says, you're wasting money unless you adjust your settings to take advantage of the fuel characteristics. This goes for any fuel, not just avgas.

I used to run my street bike on avgas 100LL, but I was a little worried about the 200 litre drum at my house, so I switched back to pump fuel when it ran out. This meant lower compression, less ignition advance and a richer carb setup. Lost a couple of ponies, and lost that delicious smell, but much easier just to stop at the gas station to fill up.