Over the years I have owned Leupold, Burris and Weaver scopes. I bought a Bushnell Elite 3200 scope to put on my deer rifle and I believe it is the very best scope I've ever owned. I took it off my Remington .308 the other day and dumb*ss here dropped it while standing up. It landed on the rim of the objective lens on a hard surface of tile. I cussed a lot, picked it up and after doing what I wanted to the rifle, remounted the scope. Took it out back fully well expecting it to be WAY off, both from taking it off the rifle and from dropping it. I had only some minor adjustment to make to get the rifle right back where it was before I took it off and there was no damage to the scope, whatsoever. In addition, I like the fast focus eyepiece on it. Any of the scopes I've mentioned are great bargains but after the Bushnell Elite, I'd have to go with the Burris. I had an issue with an older Fullfield I had and sent it back to the factory in Colorado. They sent it back, recalibrated and boxed in a new box and a blue velvet wrap. Excellent customer service.
About the 750: I think the problem with feeding comes with long action rounds. The short action numbers like your .243 and the .308 are more reliable in any semi-auto. At least that's been my experience. The 7400, in my opinion, wasn't a very well designed rifle. Remington tried to make some changed by moving the gas port 3/4" and coating the breech ramp with nickle and Teflon to try to alleviate the former problem of the 7400. A friend of mine had one of those in .270 Win. and he had trouble all the time. I like the 750. It's a gorgeous rifle. Good shooting and hopefully you'll get invited on a deer hunt. Once you've taken one, you just can't stop!!! Backstraps on the smoker just simply can't be beaten.