What about not losing Z axis position when moving?
Just a comment on that 'problem', to the effect that as much hand wringing a tooth knashing as it has accounted for over the years, if a fella simply learns to be efficient at a couple different methods of finding edges and finding centers, the issue, becomes a non-issue!
Just sayin'!

For all it gets worried about, most fellas using these mills are not constantly going from long to short and back again tooling, such that they need to worry at all about it, and I would suggest that , based on my experiences using a round column RF-30 mill, most guys are still laying out, scribing a line, and cutting to it. The extra few seconds or minutes that it takes to indicate in on a hole or feature, simply becomes part of the least part, of the work flow, and in almost all cases, simply planning your work to include say, a drill and a reamer that are near the same length, allows you the ability to swap tools and still move from hole to hole without losing anything...
And, fwiw, it's a Jet Branded model, per the label on the data plate in the picture above. (post #2). My observation of what Jet tools I have seen, has been that the are pretty much mid-pack of the Import stuff, not the worst, but not the nicest either, and priced about right for their market.