It's really a personal preference thing, I've found. I went to the Outdoorsmans a while back with the intention of buying the micro panhead, but wanting to try out all three heads they carry. When I actually tried them out I loved the pistol grip and disliked the micro panhead. I asked the guys in the shop which I should buy; one said pistol grip and the other preferred the micro panhead.
I personally believe the pistol grip is superior for using binos. It's super intuitive and just easy to use. Squeeze, point, release and you're on your target. The micro panhead was a bit more finicky with the adjustments for me, but others think it works great and swear by it. It'll be easier to pan with but not as easy to lock down in the perfect spot (that's also my opinion, I think others may disagree). It just depends on what works for you. Both are great options.