Owned the S60R for 3+ years. Got it when I moved to COlorado since my 2x4 pickup ended up stuck in a ditch the very first snow.
Luxury = S60R has clearly much more luxury features and details, but I would hope it did. The Volvo seats are definitely more comfy for trips.
Sound system = S60R had better / great stock sound system but no from factory ability to connect my iPod but I don't think the WRX's is all that bad. I am not an audiophile tho.
Ride = The Volvo had adjustable suspension, which was nice, but even the comfort setting was a more rough jarring ride that the WRX. And the extra cost for replacing shocks on the Volvo just wasn't worth it.
Power = WRX is still in break in period, but it feels faster than the Volvo not sure on the tho.
Space = Volvo has NO leg space in the back seat behind me for an adult. My wife as a passenger consumed too much space, I couldn't fit a rear facing baby seat in the Volvo, no issue in the WRX.
I loved driving the S60R, But hated owning it. Driving was always a blast. Already get the same pleasure from the Subie. Ultimately tho, I needed more back seat space adn got very tired of the constant repairs. Sure, the Volvo had 94k miles on it, but it felt like every other month I was taking it in for some sort of repair, and each time it was 50% more than the same repairs for non-European cars.
Other random thoughts
Miss the 6th gear from the Volvo
The cup holders on the Volvo were in the way of shifting, rendering them irritating at best, no problem in the WRX.
Haven't really pushed the WRX through the same turns as I used to hit in the Volvo, I do know the Volvo always felt very planted.
Overall, very happy I made the switch. Even though I really enjoyed driving the Volvo, the money pit being gone is a relief.