Pink Floyd and King Crimson aren't similar at all. Well, I can see how a fan of Pink Floyd could appreciate King Crimson, but the music is really quite different.
I'm a huge fan though, so you have my glowing recommendation to listen to it in any case.
Realistically speaking, if Pink Floyd were to unite, would you really think they could produce music on their original level?
In my opinion their last three albums weren't very good at all, so let alone what they'd be capable of now. In fact -- I personally thing that all the post Syd Barrett stuff is significantly less good. Though I must say I do really enjoy Animals and Wish You Were Here.