I am running a 6" vise with 6.5" opening, fits the machine nicely. I didn't think about it first, and bought the $140 grade vise with rotary base (you can find at various vendors). I now realize that I should have spent 100 more dollars
and bought a better grade. This one works, but not the best clamping force.
If I had money now, I would go with a Glacern , or one of the nice ones at shars.com for <$250. If you have more money, Kurt, Parlec, etc. Make sure
you get one with a large opening, it really comes handy.
The one you found looks nice, but for that money you can get a Kurt.