I operated a HP Scitex XLjet5 (solvant ink), Vutek QS3200 and the Uvistar 2, and if i had to choose i would pick the Fuji Uvistar 2 for many reasons.
1- Very fast, the media dosent move much with the freefold pinch in the front
2- for 2 side printing (recto-Verso) thats ideal, not very hard to do a good alignment and u can print an entire roll without fear. With the HP scitex, the media move whatever you doing at start, to align it properly, than you had to cut the media after 4-5 up, otherwise the verso will be off, wasting media to reload...On a vutek its very hard to do a roll to roll printing on 2 side...when i was a vutek operator i print the recto in 1 shot in roll (web) than i sheet the roll and do a verso printing in sheet mode (flatbed). Once again its very hard to align on a vutek in roll to roll printing. Thats a big plus for the uvistar if you ask to me.
The thing i hate with the uvistar, thats the multi-roll printing, if you print on 3 roll, 54 inch roll. at the same time, the stepsize (feed compensation) become unstable...for example u see white line stepping in roll 1, perfect printing on roll 2, and black line on the third roll...Its very long to adjust and its not easy. Also the machine dosent support well when its hot, lamp problem could appear.
MXM substrate are very tuff to print on that machine, the worst its probably the MXM blockout, big UV effect, like all UV machine in some enrich color u had to print in unidirectionnal to remove the effect.
I dosent like HP at all, good luck to reach someone when u had to do a customer call service, i operated a HP FB6700, the only thing i like from that machine its the last minute correction option on the work station thats it.. =P
my choice as operator are :
Uvistar2
Vutek
HP