Hamlin,
The Contender should digest those loads without a hitch. As far as deer hunting with them, the range will more-or-less be governed by your accuracy. The .45 Colt, with modern loads - NOT black powder equivalent loads- has plenty of bounce for whitetails out to 100yds plus. Trajectory comes into play much farther than that, though.
As far as sights, I won't hazard a guess as to durability. I went through a phase of trying various red-dot sights, but now all my barrels wear scopes.