Thanks for the input.

The rims that are on now are stock 18's with original 235/60R18 Pirelli scorpions. The tires need to be replaced soon and I don't have a set of winter rims or tires so I thought instead of buying black steelies, I would use the stock rims and swap out the scorpions for winter rubber.

When we were looking around for a good deal on a XC60, I came across a couple R-designs that had 20's on them and I thought they looked great. I didn't want to pay the extra money for a R-design and thought I'd get a regular T6 and buy bigger aftermarket wheels to save some money.
I have 2 850 T5-Rs as well. One has low profile tires with a small sidewall and the other has a smaller wheel with regular tires/bigger side wall. I don't find the ride is much different between the two cars but the low pros look much better.
My thought of getting 20's for summer wheels was pretty much based on how they look, thinking that the ride would not be that much different. I've never bought a Volvo as new as the XC60 (2010) before. All 3 other Volvos I've bought in the past were at least 15 years old. I figured we would have the XC60 for a long time so I'd spend a little more and make it look a little better.

I was only half serious about turning the radio up to block out wheel noise. Just trying to say that I'm not to concerned about wheel noise as long as performance and tread ware is good.