Q: will my iMac 5k run windows 10?

I have a Retina iMac 5k 3.5 GHz i5 quad core with 32 GB RAM and 256 GB flash storage. I would like to run El Capitan when it comes out, but I would also like to be able to run Windows 10 in Parallels on a different display. Will my Mac be up to this and still work fast?

I realize that we aren't completely aware of El Capitan's specific technical specifications so the alternate question is will this computer be able to run OS X Yosemite on the iMac and Windows 8.1 on a separate display smoothly?

Thank hank you in advance