I have the same vise as Stu, but with 1/2" oak on the inside of the jaws. I let the rear jaw into the bench far enough so the wooden jaw sits proud by a 1/16" or so. Loads of capacity, solid as a rock. My bench does not have an apron, though, it's 3 1/2" of Douglas Fir.
I see lots of setups where a modern quick-release type vise is buried in massive wooden jaws - seems to be a recent fashion. It gives a more traditional 'bench screw' look to a bench, but you pay for that in capacity. If I want to spread the force of my vise jaws around I just stick a couple of pieces of dimensioned lumber in there temporarily.
All the best,
**Now holding auditions for a catchy new signature**