So I've been waiting to have these put in my flying v (Gibson gothic v) for awhile but I finally received the rest of the parts I needed for my guitar overhaul. I have another V loaded with a Duncan Invader in the bridge and a Rio Grande bar-steward P90 in the neck (I use the neck for clean tones so I like single coils typically).
The Invader seems to have a bit higher output and pushes the amp a bit harder than the Warpig. The Warpig has a tighter, more solid low-end thump to it compared to the more rounded (though still fairly tight compared to say PAF's) Invader. In fact the low-end in the Warpig is absolutely the most massive and tight thing I've ever heard, it even holds up under my baritone tuning (BEADF#b strung with 14-68's)....it's also a bit odd that it still sounds very balanced. There really is a nice quality of clarity here that is also surprising. The highs are sweet and crystal clear with the pig. The Invader is more aggresive sounding because of the emphasis on the low-mid's so things like pinch harmonics are just a bit easier than on the warpig. When chugging away on chords on the E and D strings the warpig's low end is still very nice but never over powering or artificial sounding, everything is in great balance.
The neck pickup of the warpig was really sweet sounding when coil tapped...this was probably the most surprising thing. While it sounding confuse anyone for a Strat there are few things more beautiful sounding than a baritone tuning with a clean single coil.
Overall I like the compliment of my invader v and my warpig v. Aggressive, crunchy mids with the invader and crushing low's that sound bigger than anything with the warpig. I have a feeling that at least for now the v with the warpig's will probably get the most use :)
Now if I can just locate a set of Mississippi Queen's in the US...I have a semi-hollow that will really benefit from them.