I recently got some Urethane covered dumbbells and was so impressed with them that I was looking to upgrade my weight plates as well.
I did a little shopping around and found that Troy makes these. I have the regular grip plates from them and never had any particular problems so that seemed like a good choice.
Placed the order at GTech (fair price and even with free shipping)! They arrived quickly without any problems and I love them. They feel incredibly solid, make very little noise when in use (got a home gym, so low noise is great for when the kids are asleep), and the urethane covering feels like it's going to last a lifetime.
I did find a plate missing when I got the shipment, but Scott at GTech got me taken care of right away, and I'd have to say that their service is simply fantastic. I'll definitely be doing more shopping here.