I've always been into wahs because I started playing guitar because of Steve Vai and then almost immediately discovered Metallica. I agreed with everyone here that Steve is perhaps the prime example of tasteful wah use; sometimes I don't even realise he's using it! I get the wah-abuse banter, but I think some of Kirk's wah-based solos are relly well executed and would sound rather boring/soulless without a wah (especially the ones in The Black Album and the Load/Re-Load* era). My favourite wah moment in a guitar solo, however, is in Kreator's song Phantom Antichrist, the lick at the very end that repeats under a wah sweep—simple yet genius! Guitarists in my other favourite bands (Slipknot, Mastodon, Lamb of God) also use a wah here and there, so I've never been averse to it.
I bought the usual Dunlop Crybaby 95Q as my first wah ages ago and it's been a constant companion since then. I also got the standard Crybaby but that doesn't get much use. I've also owned the Morley Bad Horsie which I bought used in 2014-ish. It wasn't very comfortable to treadle and so it has been sitting around somewhere in the house. It sounds cool but the travel is not something I can get used to. The angle is just too steep.
I also have the standard Cryababy mini, the 535Q mini, and the Crybaby Jr. These days, the Crybaby junior is my go-to wah because it is the goldilocks size: not as big and heavy as the usual crybaby, but not as tiny as the ankle-busting mini. Came highly recommended in a rig rundown from Paul Gilbert, who had one on his fly-rig. And it's True Bypass, which is why I prefer to have that over the 95Q these days.
The fractal wah block is pretty good, too, IMO. I have a spring-loaded (like the 95Q) Mission Engineering EP-1, which makes using the Fractal wahs a breeze.
*I think those are the best sounding Metallica albums they ever made, btw. The guitar tones on Load especially are fantastic, even better than the Black Album, IMO.
