I had wall to wall carpeting installed almost 5 years ago and I am still pleased with the results.
My only real issue is that I had to remove all of nails that were in my hard wood floors myself before having the new carpet installed. I was told that if I didn't remove the old nails/staples, the heads/tops would be cut off and the metal stems would forever remain in the wood. This would have created a problem if I ever decided that I wanted to refinish my hard wood floors, so I'm glad they told me up front.