It took me one 10 mile ride to get used to them. Didn't need to adjust my saddle.
The "hard to control the bike" concern is overstated. It's not like when you install them you are automatically required to ride on them constantly. It's pretty simple: when you're in a group, stay off them.
I hope the Di2 comment was a joke. Again, if you're riding somewhere where you need to brake and shift a lot, probably don't need to be on them. For long flat stretches where you can see ahead, they're good.