I've been using a 6x40 Springfield on my .270 the last 4 seasons, simple is nice too. Works just fine out as far as I need in Hill country, 200/300 maximum but typically under 150 yards. If I can swing it , next season, I will go to a 3-9 x 40. Bigger scope power like magmun rounds, bigger is not always better.

If you can properly gauge the hold over of a particular rifle on a deer 500 yards away with a 6 power scope then God Bless you. I'd say most cannot.

I have a straight 6 power scope on a 243. But then I'm not going to take long shots with a 243. Can you hit a deer sized target with 3, 4 and 6 power scopes at 300 yards? You bet. I've done it. Can you know exactly where you are placing that bullet behind their shoulder? Nope. If you want to shoot precisely you have to be able to aim precisely. That is why I will always favor a variable power scope unless I am putting together a gun/scope combo that will be used exclusively in short range hunting situations, like a 30-30, 35 rem, or 45-70.

I usually try to match the scope to the gun ,If the gun is capable of 400 yd shots then I want a scope that is equal to the task . I wouldn't put a3X9 on a 22 lr or a fixed 4 on a 300 Win . Mainly it's a matter of preference but I have a few of the bigger scopes and find they all have their place.