I went with Ubuntu on two of my computers, and planned on a third except I couldn't get it to run at all.
From my experience, Ubuntu is an unpolished and buggy piece of crap. It seems to break constantly, has some really awful user interface choices (when a fullscreen program crashes on you, good luck). It seems to lag the entire system when it is trying to do anything big, instead of breaking it into smaller pieces. And almost everything seems to count as one of those "big" processes. It doesn't have decent touchpad support, and the list just goes on. My whole experience with Ubuntu was an absolute mess and consisted of a ton of staring at a frozen Ubuntu while it did god knows what (quad core 2ghz and 8gb ram shouldn't be like that).
The worst part was that I had originally been sold on Ubuntu after reading about it online and had convinced two of my friends to try it out. I feel awful for helping them install this stuff on their new computers.
It is not a question of whether or not Windows 8 is better than Ubuntu, the question is if Windows 8 is $200 better than Ubuntu, which I think can go either way. The hassle that Ubuntu caused me probably warrants the extra cost, but I found that Ubuntu never even really behaves too consistently. Different things were sometimes broken or not broken on each startup, so maybe it is worth a try to see if it works for you. If it worked perfectly I would say to go with Ubuntu.