Higher compression is good - and bad.
The good is that you get more squish of the fuel and the air - which in turn, generates more power. The bad is that it causes more heat, takes more juice for your starter to turn over, and if high enough, can lead to detonation problems.
I didn't have any detonation problems once I dropped back down from my 11:1 piston to my current 10.5:1. The best offset for detonation is higher octane - which is more expensive and more of a pain to either mix or find.
Back on track. A good machine shop will only bore your cylinder to match it to the piston you provide them. If they say they'll just do it to whatever spec the book says, move on down the road and find another shop.
Boring won't decrease the longevity of the cylinder - it just reduces the number of times it can be bored later to clean up an out of round cylinder or some light scarring.
A 0.010" over bore is a nice cleanup and does require a new piston and rings. It can put most machines back into "as good as new" condition for the upper end. Keep in mind, you want to make sure your valves are in good sealing condition while yer in there. A nice lapping is pretty easy.