Came to say this. DKCR looks just as good on 3DS as it did on Wii.
Wii version looks better due to higher resolution. The rest looks pretty much equal. Anyhow, the Wii didn't exactly have games that had graphics that are significantly better than anything on Gamecube. Gamecube came close to Xbox in terms of graphics and not a single Wii game looks as good as Ninja Gaiden (Black) and Splinter Cell: Chaos Theory.
Read the mania: http://www.fanfiction.net/~nonexistinghero In SA2, it's Super Sonic and Hyper Shadow.