it will enhance your ride. A buddy of mine had 17's on his Audi A3 and due to the harsh ride, decided to go to 16's.
Totall different car, but it's really dependant on what you really want.
I have 17's, and their huge. Rears are 275's. It makes for a bit of a rough ride, and pulls me around a lot on the highway. But only drive about 13,000 KM's per year so no worries for me.
post some pics of them.