Considered one before I bought our current trailer sailor (a Nimble 20). Considered somewhat similar to a Compac 19 (shoal draft fixed keel).
IMO big plus to them (other than looks, which is subjective, but I think they're good looking boats) is the outboard is in a well, much less likely to cavitate in swells than a motor off the back. But does mean you can't raise the outboard when sailing, so a little extra drag.
They can be tender because the keel isn't very deep and that also affects windward sailing ability.
Biggest negative I've heard is they're not particularly heavily / well built. The keels in particular are known to have not very thick layer of fiberglass around them, make sure you're not getting any water intrusion into the keel / ballast area. People have put an extra layer of glass on the whole hull I think.
There were a few different styles made, I believe... the somewhat "standard" and then a cuddy cabin with smaller cabin and bigger cockpit.
There is a Skipper 20 Yahoo group that might be able to help with specific questions:
And some good general trailer sailor help here:
Where do you plan on sailing it? Lake, ocean?