I'm 6'3" 185 lbs and have skied all those. Here is my breakdown for you:
Pistols: Sick as fuck everywhere. I had 179s and they had great float in the pow, easy to spin in the park and super quick to turn in tight trees. Not to mention, you can also find the steepest line possible and just straight-line it. This is one of the best skis out there if you want one ski that can do it all. Also consider the Vicious, which is a new, and better, version of the Pistol. The tail is stiffer, so more stability and the progressive sidecut makes it that much more versatile (I have 189 Vicious, but have not had enough time on them to give a valid review).
ARV 185: I don't have as much time on ARVs, but they are a great ski too. Plenty of girth for pow. Also a bit stiffer than the Pistols (at least the 03/04s were). I don't think they turn and hold an edge as nicely as the Pistols, but still a great everyday ski. Also, they are pretty light, so pretty good in the park and in tight spots. I also like the size of the 185.
MSP 187: I skied a pair of 187s for a few days this season and was entirely unimpressed. However, in all fairness to 4frnt, I think they were mounted in a spot that did not suit my needs. They were mounted at freeride, but if I ever owned any, I would go further back than that as it felt way too centered for me (I spend much more time outside the park than in). On steeps I found the MSP throwing me forward, which I taly up to the mount point, but it wasn't enjoyable all the same. On the groom, I disliked the sidecut as well as turn initiation was not nearly as easy and crisp as the two skis above.
Anyway, that's probably enough info. Hit me up if you have other questions.
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