For your .270 rifle it would hard ................... very hard to go wrong with a good fixed 6x scope. Specifically a 6x42mm allows good all round useage. I use a 6x42mm Schmidt & Bender and have another 6x42 Deutsche on another rifle. Also have a 3-9x42mm Lisenfeld which is set on 6x
Now on the varmint type rifles
I would go for a varible scope as you are more likely to use the higher power magnifications when using it on small varmints but again 6x is plenty for Coyote and Fox
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As several have already stated good quality optics are a good investment as you can see the little things more clearly
and you cannot shoot what you cannot see
Now I know that they are getting into the US more now but the Meopta line of scopes is well worth a look. They come for the Czech republic and have been making scopes fro a long time
I have a couple a 7x50A and an old 3x which was meant to fit a Brno ZG47 rifle. Good luck with your choice and let us know how it works out.