XC90 2013 - anyone fitted 20" wheels?

Just bought a XC90 2013 sporting 235/65 x r17 tyres. I know the R-Design has 19" wheels. I'm looking at the feasibility of fitting 20" alloys to the car with 255/45 20 tyres. Has anyone done this? Which alloys are suitable....eg avoiding wheel arch fouling. The tyre size is the same circumference - just not sure about offsets.
I'm used to lower profile tyres on my modified RAV4 and so got used to it sticking to the road.....the XC90 is a bit squirmy with the 65 profile tyres.

Pics of any conversions would be helpful too. Thanks

(I tried searching this forum but couldn't find any info.