I'm going through about the same thing right now with my .50 Beowulf... Trying to decide on an optic is not so easy! Like you, my .50 will be for hunting, whitetail and hog, and considering the round and the area I hunt, 150 yards will be a LONG shot. I looked at most of the options and the Leupold M8 2.5X20 really has my interest right now. I plan on an extended rail to get the scope a bit out over the handguards and into a proper position and like you I don't see the advantage or point of a high magnification/large objective scope on these types of weapons, I'm more interested in a solid, reliable scope that can take the recoil and not come apart in a few years. The Leupold 2.5 sees a great deal of use on heavy recoiling dangerous game rifles and their warranty can't be beat by anyone...
I'll be curious in the replys you receive as well...