I have the Dremel plunge base, and about the only good use that I've found for it is rapidly drilling through holes in scroll saw projects to feed the blade through. The Stu Mac version is much more precise, although considerably more expensive. If I had the need, I would likely try to make one similar to the one that Harry posted. Notice the wing nuts above and below on each post. This will stabilize the base at any height desired. Not as great for some uses as a plunge base, but way more accurate than the Dremel toy if you can do without the plunge option.
Central North Carolina