Like Warren, I found that I need to have my vise at the right height or else my shoulders hurt.
The best way to get the vise where I want it by using a clamp in combination with a Dyna King right angle vise extension. They have two types, and adjustable and a fixed extension. I use the adjustable version with my Dyna King and Renzetti vises. I need the vise to be low, so with a high table, I can actually place the extension in the underside of the clamp, swing it out from the table and put the vise in the extension. On my tying bench the vise jaws are actually at the level of the table top but about 8 inches away from the table.
I also have a base to mount the vise if I need to use it where a clamp wont work, but the clamp in combination with the right angle extension works best for me in most cases.
As for the use of the Clamp, … I seem to prefer it as I really have to adjust the height or else I get a knot in my shoulder (old age setting in).
I also always have a board, scrap of plywood or a cutting board somewhere in the truck, so setting up river side isn’t a problem. (The picnic tables ae just fine too).
I’ve never tipped a base on the Regal, Peak or even starter models with less expensive bases. BUT . . . if you’re tying bigger flie, saltwater, bass bugs, lots of spinning of hair, etc., it may make a difference. But for everyday general tying, the base should be fine.
Of course, if you’re drinking a lot while you’re tying, all bets are off!