First things first:
It will NOT print a full 4x8 panel without some serious tinkering. We've gotten close to a full 96" run with a sled on the front and the back, but without that kind of serious fiddling, you're going to have to settle for 46" by 92". Max.
This printer is HUGE. I mean absolutely HUGE. You add the tracks on the front and back for printing on panels and its footprint is close to 12' x 20'. Seriously. Also, transitioning from roll printing to panel printing is a process of about seven steps, but it's really not all that bad once you get used to it. Storing the hardware on the other hand is a serious pain in the ***.
This printer sucks down ink like nothing I've ever seen, and I've been doing this for a while. We've been dealing with a major event this past week, so our usage has been heavy, but we blew through three 220cc Magenta catridges in a DAY (those are like $100 a pop). Also make sure that the people who sell this printer to you actually keep the ink in stock. After the first day we had it set up, our 640 was down for about three or four days because our distributor didn't have the ink in stock. The excuse was that they don't like to keep the stuff on hand because the shelf-life of UV ink is only about three months. Yes, hell was raised.
Buy the air-cleaner. It works great, and without it, the stink this thing puts off will cross your eyes, and probably make you sterile.
There is NOT a USB port on the back of this machine. Ethernet only.
Now, the good stuff.
The print quality, even on high-speed, is pretty damn good.
Speaking of high-speed, on the fastest print mode this thing will hammer out a 4'x8' image in a shade less than twenty minutes. We plowed through what used to be a twelve hour run in a half a day with this printer.
If you're printing designs that are not full-bleed, it's actually fairly reasonable with ink usage. I got a set of six 22x28 Sintra panels out of it in about 6ccs the other day. Not as frugal as an inkjet, but we're also not paying for decal material, laminate, or the labor to do anything beyond cut them apart.
Versa Works is simple. It's not a jangled-up mess like Onyx and it doesn't have the two or three huge irritations that RasterLink does. This is, admittedly, the impression of someone who's only used this software for a few weeks, but so far so good. I'll let you know more once I really start messing with the white and the gloss inks next week.
TL;DR:
There are some gotchas, but if you've got the cash, it's a buy.
*EDIT*
With a belt-feed (which you cannot get aftermarket, a printer like this either is or isn't belt-fed) you apparently CAN print a full 4'x8' sheet edge-to-edge-to-edge. However, ask your dealer about this, and have them do a demo before you buy based on that qualification.
