I spoke with a very experienced photographer friend today, about my clogged or damaged LLK 7900 channel. He responded, and gave me his permission to post this. He's a photographer, but he's actively engaged in a business that prints in high volume; mostly on canvas. I'm not trying to stir anything up, with brand wars, but earlier in this thread, when I read the post about the design differences between Epson, Canon, and HP, it tweaked my interest. If I chuck this 7900, and start fresh with a 44" unit, I don't want to make a mistake. I've always been an Epson loyalist, up to this point. Below are his comments:
I use the HP Z3200ps. It has a built-in i1 spectro and all the software needed to profile anything you can put into the printer. Great advantage. One thing I'm hoping to do is trying the emulsion you shared a link about. You can put that on a piece of sheet aluminum (or any other substrate) and this printer will do a great job profiling it.
Also, the Z3200 doesn't need a "wasted ink" tank. Nothing like it on this printer. To me that seems to be a much better design. In the 14 months since I bought it, I have not had to perform maintenance on the printer once. Instead, I leave it on all the time (per their instructions) and it goes through a routine every once and a while to keep itself in tip-top shape. My Canon is different. Has a maintenance tank, but still keeps itself in good shape, sometimes pausing before printing to check and make sure.
The HP printer comes with a maintenance contract for the first year. I extended it for another year in January, and will continue doing this as long as I have it. I just don't have the time or interest in tearing my printer apart. Use to be gang-ho for anything, but I'm focused on being productive, not saving money to keep the printer running. When I first got it, something didn't work right and they systematically replaced every single component in the printer until the problem was solved. Turns out the cause was my using illegal characters in naming profiles. So they replaced 100% of the components first, and then started looking elsewhere. Impressive.
All that was done under warranty, and it taught me a very valuable lesson - let the pros do it.