I've only dabbled once with a chassis, an MDT LSS on a Rem700. I used it for a season of coyote shooting. IMHO it just isn't a practical hunting rig; too heavy, certainly less convenient for sliding into some storage crevice in a truck. The chassis was okay for bench shooting, but for any real-world field position I never found it as comfortable as a traditional stock. DBM is common today, so that feature alone isn't really a selling point for the chassis.
The only possible advantage of a vertical pistolgrip for hunting is in situations where you might be down "on the gun", ready to shoot, for an extended period; in that case, the vertical grip eases tension on your wrist and is quite nice. Examples would be hunting turkey or coyotes. For me, however, the cons outweighed the pros; the look-cool factor fades away quickly when faced with actual use.