Although I'm mostly an "amp distortion" kind of player, I thought about doing this shootout for a while, and specially when the drive models were "G3'd" in firmware 19. This is a general overview, not an exhaustive one, as some models works better as boosters, others as drive pedals in clean amps ; and some pedals works better with specific amp models etc. : the Xotic BB Preamp works great on a Mesa Lonestar (Andy Timmons), MXR Distortion+ on a Hiwatt (David Gilmour) etc...
Here's the timeline of this demo :
0:00 The "BB pre" model in a slightly tweaked stock preset (I only touched the delay and reverb settings, amp and cab are stock) (also check this thread : http://forum.fractalaudio.com/axe-fx-ii-preset-exchange/101673-what-some-tweaks-can-do-stock-patch.html )
0:59 Various drive models as distortion pedals in a dual clean amp custom preset
5:57 Various drive models used to tighten/boost high gain amps. I used a "Rose of Sharyn" DI track for that.