I personally like a "Mechanics" vise with an anvil surface for hammering. A true "machinists" vise is designed strictly to only hold a workpiece and certainly have their place, however, for my uses, the anvil surface is extremely handy. At work, we have several large Columbians without an anvil and a Wilton Bullet with one. I find myself using the Wilton more often than not.
While a nice feature, I don't miss it since none of my vises have an anvil back. Nor do I find myself using on any vise at work that has one. For my beating needs, a heavy steel workbench works just fine.
I have both a large Wilton bullet vice and a 3' long piece of railroad track that I found in the street one day. If I need to really lay into something with a big hammer I'll use the r.r. track.