I tend to use the Hoya Pro HMC filters. Are they better than the cheaper alternative, I honestly can't say. However If I've just spent £500-£1,000 on a lens I don't want to be constantly worrying about the quality of the filter on the front. The price difference isn't all that much considering the cost of the lens
I think the Pro is thinner as well. Ideal for when you have a polariser on the front of a wide angle lens