I won't tell you what to buy as there are good recommendations here already, I use a Diavari 1.5-6 on my 375 and love it, will never change it. I have used a lot of low variable Leups on 416s, 458s and 450 Ack and never had a failure. The one to stay away from is Swarovsky, they will not warranty a scope mounted on anything larger than a 338. My buddy found this out the hard way on a 416 Rem. Their literature even said this in the extra fine print, which none of us read when buying a $1200 scope and we just assume the warranty is all inclusive.