Digital BW, The Print

I have not been following the group for the last few months so I 
don't know if this has been discussed but I am having nothing but 
trouble with a newer cis sysytem for the 1280 I purchased from MIS. 
Previously I had been using a CIS that had kind of a wand that 
suspended the tubing over the print head-for about a year trouble 
free. Because of a blocked black I replaced the whole system with a 
unit from MIS that has kind of a plastic bridge  that holds the 
tubing over the head. Nothing but trouble- jets glogging yellow goes 
out-black jams then they all reappear for a few prints and start 
disappearing again. I'm beginning to think over all that this is a 
really inferior system. Ay one else having problems with MIS cis?
UT2 on a 1280. Already on a second set of carts in less than 5 
months...
Jack