Here is a photo of my Grizzly mini-lathe and HF mini-mill in my former basement shop. I bought the HF mill for the R-8 spindle. Its on a standard Craftsman workbench and there is an Enco catalog on the shelf above it for size reference. I think the bench is right around 60 inches long.
I hope this helps. Of course, actual dimensions and (more importantly) work envelopes are available on the web sites of the various companies that make these. For a given specified work size, they are all pretty similar (ie the 7x10's are not quite comparable with 7x14's, but any two makers of the 7x10 make units that are about the same physical dimesions.