Since you're looking at doing 4 color, I imagine speed is the goal. Based on both companies specs, the Mimaki is the clear winner.
LG-640 343 sqft/hr at 720 × 600 dpi
UCJV330 592 sqft/hr at 600 x 600 dpi (2 pass)
or 440 sqft/hr at 600 x 600 dpi (4 pass)
If done properly, it should work fine. They're probably just worried that the head might not make it through the process properly and then will need to send you a big bill for a new head. I always tell people that want to change ink configurations like this to be prepared to need a new head and if they can't or don't want to afford it, don't do it. But if the head is in good condition now, all nozzles are firing, a proper flush. ink line configuration, and ink fill up should do the trick.Gotcha — just to clarify, I wouldn’t be doing the changeover myself. My dealer is saying it’s better not to mess with it at all, even if it’s done professionally, since it can lead to issues later. Do you agree with that, or do you think it’s fine as long as a tech does it right?
You know that UJV100 can only print white under or over the color? It can't do both. It's decided when installing the white ink.Gotcha — just to clarify, I wouldn’t be doing the changeover myself. My dealer is saying it’s better not to mess with it at all, even if it’s done professionally, since it can lead to issues later. Do you agree with that, or do you think it’s fine as long as a tech does it right?