haven't done it yet but am seriously contemplating starting a Dr. Slump collection.
I picked up several volumes from the last TRSI Viz manga sale. However, I quickly found out that volume nine is out of print, and commands a rather hefty price from other vendors ($40 and up). I'm still looking for an inexpensive copy, or holding out hope that Viz will do a Big edition of Slump.
i actually found a a number 9, im seriously debating taking the chance and going ahead with getting it. it was about 7 bucks i think. i ordered num,ber 1-4 for now. I agree the big edition ide though. they need to . They also really should get that anime over here.
I also picked up
Kare Kano 1-3 collection
and will prbably be ordering the first two Lucky Star mangas once volume 2 comes out.