You can bookend my 30 years of woodworking with two volumes. Roy Underhill’s “The Woodwright’s Shop: A Practical Guide to Traditional Woodcraft” (U of North Carolina P) marks the beginning. Today, Steven W. Semes’ “The Architecture of the Classical Interior” (Norton) makes sense of all the conflicting mishmash of “design speak” tossed about. Hope I have another 30 years in me so the Semes book will someday be a midway milepost in a long, rewarding journey.
Drilling a precisely positioned, deep, wide hole isn't easy, without a drill press. So I bought a WolfCraft drill guide. After experimenting with it, and drilling some test holes, I build a jig around it. I screwed it to a scrap of MDF, and then drilled a carefully-centered 3/4" hole. The MDF can be clamped more easily than the base itself, and the 3/4" hole will keep a 3/4" Forstner bit drilling precisely where it is supposed to.
Remove the jaws and route the edges that you could not route while they were still attached. Then use a roundover bit on all of the corners except the inner edge of the inner jaw of the end vise. Give everything a lite sanding, and apply Danish oil to the inner surfaces of the jaws. (By "inner surfaces", I mean those surfaces that will not be accessible when the vises are assembled - the inner surface of the inner jaw, that bolts to the bench, and the outer surfaces of the outer jaws, that bolt to the vise plates.)
A better solution would have been to route a rabbet into the side, so that the added strip always had thickness. The way I did it means that the strip I glued in is very narrow, and hence very weak, at a certain point. In this case, that's not a problem, because it's going to be sitting under the countertop layer. I also noticed that because I had only clamped the strip down, and not into the edge, there was a noticeable glue gap where the strip butted up against the MDF. Again, in this application it isn't visible. But if I was doing something like this on the top of a table, I'd make sure to cut a clean rabbet, and to clamp both down and in.
While a strict figure for the bench’s weight capacity is not available, a quick browse through their other stand and bench products shows a general weight capacity well above most other brands. As such, while we cannot say for certain that this bench provides the best weight capacity, it is more than likely that it the capacity is similar to the other products in the catalog.