Since your question's been sitting here a couple days, I thought I'd offer a comment. I haven't used the Burris red dot, but I'm doubtful it would take 270 gr. loads for long.
My 12" Contender wore a 2X Leupold for the first couple years and has had a 4X Leupold on it for the last 15 or 16. I changed it to a 4X when I realized that the .375 JDJ was accurate and flat shooting enough to deserve that level of magnification. My 15" Encore started with a 2-7X Burris, but I changed it after a couple years to it's current Bushnell 3200 2-6X because it weghed less and performs well. Both guns and scopes have withstood 220, 270 and 300 gr. loads well. The Contender has been carried over much of the world hunting.
I have a lot of experience with Ultra Dot and Millet Red dots, mostly on revolvers and .22's. That experience has been good, but frankly I don't "get" putting one on a .375 JDJ...I think it deserves more. I did have one Ultra Dot fail on a very short barrel .45-70 Contender. It took about 60 rounds. But, to each his own....