I did a quick lookup on one commercial load for 270 WSM with a 140gr bullet and it requires 13.75 MOA elevation adjustment and 8.25 MOA for a 10mph wind at 600 yds.
Another load showed 9.25 MOA elevation and 3.75 MOA windage at 600 yds.
I don't know if I'm looking at the correct model number for your scope. But, the following url shows specs for a VX-3 3.5-10x50mm...
Leupold || VX-3 3.5-10x50mm
The model I looked at in the above url has a 1 inch tube with 57 MOA of elevation adjustment. Half of that adjustment will be up and half down. So, you should be able to come up about 28 MOA before you bottom out which would get you to about 800 yds with that first ammo and severly limit your windage adjustment which is increasingly important at longer ranges.
So, you could probably shoot to 600 yds just fine with standard bases. But, a 20 MOA base will give you extended range and I've observed no disadvantages with 20 MOA bases on all of my rifles.
I prefer EGW one piece picatinny 20 MOA rails and Burris Tactical Elite Rings as a reasonably priced option of good quality. These also make the scopes easily interchangeable between rifles.
Removing and replacing the scope on the same rifle won't give you an exact zero. But, it'll be close enough that only one or 2 shots will be required to re-zero. Changing rifles may or may not require bore sighting. But, you will definitely have to sight in your rifle. In either case, you may never have to re-adjust your rings once set up correctly.
Hope this helps and curious to hear what others think.