There has been a lot of marketing over the past two decades to sell "new, more vintage-correct" wah pedals from every company under the sun. Chances are, if you're listening to a CryBaby wah on a classic rock or metal record, it's one of these. They're not the most "vocal', or "soulful" or all the other BS terms that guitar forumites use to justify their new $200+ wah pedals. But they have a certain magic, and mine cuts through the mix and sounds just plain mean. The buffer isn't the greatest, but a decent buffer pedal before and/or after the wah will clear up any tone-suck it has going on. I've tried lots of different wahs, a few recent era Vox's and countless Dunlops - this one just has THAT wah sound, the one you've heard on records by Zeppelin, Metallica, Motorhead, etc.
What else can I say, this thing sounds amazing. Probably because it's the same brand we all grew up listening to. There's a great article here on Equipboard about the Cry Baby wahs, recommended reading. My understanding is there are different components in the versions, like the Halo vs the Fasel ...er, transducer? inductor? I can't remember but some players like the Fasel while others like the Halo. And there are red Fasel and yellow Fasel, and then there's other models with something else entirely. Do your homework and play as many as you can before buying!!!!