Digital BW, The Print

I would love to know the consensus on black and white printing a year later....I 
followed this forum about that long ago and decided to buy Lyson Quadtone 
Inks and an Epson 1270 as a second printer. I print mostly portraits on 
watercolor paper. I loved the prints - however, to my horror, I had a client call 
and tell me their prints were fading - not even a year later. So, then I started 
using my Epson 2200 for my black and whites, but then you deal with 
metamarism. THEN, I started printing black only on the 2200 but have some 
banding issues from time to time.

So, I'm back where I started. I would like a simple system to print Black and 
white images and am willing to buy a second printer to do so. Archival quality 
is very important. What is the latest school of thought on the best, long lasting 
black and white prints?

MANY, many thanks,
Lynne Siler
Asheville, NC