I would imagine that the noise comes from the tire rubbing on the fender and squeaking. I would think that some kind of material could be placed in between to eliminate that.
Personally, I like the side mount if it is on the driver's side. That way it isn't blocking much view. It is much handier when you do have a flat and don't have to crawl under the truck and get quite as dirty.
The biggest problem I have with the side mounted tire is that it seems so many people never have a matching tire/rim. That makes them look bad. Many people use old tires for a spare also. Bald tires don't look so good when it's in view either.
