Tweed, you sure the Regal is steel? Thought it was nickel-plated brass.Tried the Regal, Johnson and Dean at Elderly last year, and the Regal was by far the best. The Dean had a thinner sound, and the Johnson sounded muddy and unclear. The Regal had the best depth and clarity of sound, and a great sustain. So I bought it! :-) Nationals sounded better, but at the price they should - the price was 4 times more though, and they certainly weren't 4 times better.
One note of warning - I've had some problems with the Regal. The bridge warped a bit, which screwed up the tuning. Elderly were good about it though and sent me a new bridge free of charge. I also have an intonation problem with mine which I can only fix by taking the neck off and shimming it out (so I've not done it yet!). I would recommend that you compare the 12th-fret note against the 12th-fret harmonic, and reject any guitar where the two don't match for all strings.
If you search for "resonator" or "reso" over the last couple of years, you'll find a bunch of stuff. "reso" will also show up "resolution" which comes up every New Year, but I'm sure you can figure out what's worth reading. :-)
Oh, and don't forget to run it with the heaviest strings your finger can manage, to get that nice rich tone.
Graham.