RE: Is an Adjustable Objective nessasary.
Depends on your shooting form, what you want to do with the scope and how far you plan on shooting. For a target scope or long range varmint rig I like them. For large game hunting don't waste the money on it. For one you don't need that much power and you don't need the precision of a parallax free shot at normal hunting distances. Now if you hunting long ranges like 500 yards and out then it might be a consideration. However out to 200 yards or so on large game it simply isn't needed.
Paul