Bob,
One thing to consider when you are thinking about a used large format printer is if will it need
to be tipped up to get around a corner, up/down stairs, ect... Once these things are charged with ink
tipping them beyond a certain point can be a big problem. In some cases it may be cheaper to buy a new printer
than purge and refill the ink to move it.
I own both a epson 7900 and a canon 8300 and am firmly in the camp that the canon is a much more user friendly experience
than the epson. I also have a epson 3880, like you, it is pretty much problem free compared to the 7900.
Its nice to have a warranty on a new one, you could find yourself buying someone else's problems buying used.
Both companies frequently offer rebates that reduce the cost quite a bit.
It was good to meet you in Park City. Glad you were satisfied with your sales there. For me it was an all time record show:-)
You probably shouldn't expect other shows in the area to be as good. Like I said, you jumped into the deep end of the pool for a first show.
That show is probably one of the top 10 in the country.
Good luck,
Bill