Digital BW, The Print

I've been very pleased with the look of the prints I've made with 
QTR. For someone who prints both color and BW it seems like the way 
to go. I am concerned, however, with mention I've seen here about 
possible problems with differential fading of the various color inks 
that are combined to create a bw print. I've also heard mention -- 
can't recall where, perhaps photo.net -- that some galleries do not 
accept bw prints that are made with a RIP using the Ultrachrome 
inkset. I'd appreciate hearing any information or opinions about 
these issues.

Chris Hargens