I'm just not a fan of making "unmatching 
matches". I just can't see bringing together a cel 
with a background it "never knew". There are 
certain ebay sellers that almost always match 
their cels to an unmatching bg, and I tend to 
never buy their stuff, because many times the 
gouache paint from the added background can leave 
scuffs or markings on the cel's acetate, and I 
would certainly be seperating the pairing. I'll 
admit I've seen aesthetically nice looking 
nonmatching pairings done, but if it were mine, it 
would always nag me every time I looked at it. I 
also wonder about the backgrounds- "Who do you 
really belong with?"
Blair