I have a 2012 MBP with Parallels. Speed doesn't seem to be an issue; I use it for Crestron, CCTV and more. It will sometimes run warm though, and the fan won't slow down until I close Parallels. I never really looked into what else might be running in the background that might cause that.

I got that MBP about 4 years ago certified pre-owned from IBM, and it was solid until about 7 months ago when it started acting weird (screen wouldn't turn on, random crashes), and eventually the logic board went south. I don't know if it's related, but I can't imagine the heat being good for it.

So if you find yourself turning up the volume on your YouTube video because the fan is too loud...well, you might want to check that out!