Serrated wheels cut faster/more aggressively, but leave a rougher finish. Smooth contact wheels cut slower/less aggressively, but leave a better finish.
Personally, I feel the best "bang for the buck" when it comes to contact wheels is SunRay. There are a couple of things you need to know though.... Sunray produces urethane contact wheels (which I like better then rubber), and they only build them to order (they do not keep contact wheels in stock). Contact wheels are a "side line" for them, as their main function is as a military contractor. This brings up another caveat.... When ordering from SunRay, you MUST specify ALL the information about what you want....being a contractor, if you don't ask for it, they don't do it. For example, I suggested them to an individual who placed an order for a 12" wheel. After he received the wheel, he called me up, fussing about how Sunray did not balance the contact wheel..... when I asked if he had specified "balancing"....his response was "No! They should have known to do it!" Like I said, they are military contractors...if you don't specify it, they don't do it!
The reason I prefer urethane over rubber is that I find it more durable, and more consistent. I also like the fact that over time urethane does not "dry rot".
I've not looked in a while, but I believe that USA Knifemaker stocks at least some urethane wheels from Sunray.....might be worth a look.
