For most people, it's not really recommended since you can easily damage the GPU die if not careful in the replacement process. Will an aftermarket cooler reduce GPU temperatures? Yes, for sure. Unless you're an experienced user I wouldn't go this route, instead purchase a card with an aftermarket cooler already installed.

Aftermarket coolers are fine, but most don't use them, since today's video cards come with excellent coolers. I would recommend to avoid the hassle, spend a bit more a a video card with a better cooler. Another reason I like HIS video cards.

Nice. Thanks.