I actually had the opposite problem.
I bought two complete douga sequences of Saiyuki.
I was wondering whether it would be a good idea 
to split them up...
I thought it was cool to have the whole sequence, 
and it seemed sort of wrong to seperate them. I 
didn't actually *want* to get rid of any, but I 
don't have a whole lot of money to put into this 
hobby, so in the end I decided to trade some of 
the fillers so that I could put more variety in 
my collection. I debated over this a lot though 
before reaching my decision.