Depends on the wah sound you want. If you don't mind a sound that is (in my opinion) a bit characterless, then go for a morley. I had one and hated the wah sound. The only real good thing about the bad horsie is that you don't have to turn it on and off manually. The pots also last longer before going scratchy(which is no real big deal in my opinion).
If you want something with a bit more of an own voice then try out a cry baby or a vox, the vox limited edition wah's are nice as well due to their extended range (been using one for years now). The dimebag signature wah looks very tasty though, and I am considering splashing out on that...
I think that roland makes a v-wah (wah modeller) that sounds quite good allegedly, and there are also several boutique wah pedals out there to have a look at.