Well, I bought the Classical Puppets bell shaped petticoat here http://clobbaonline.com/index.php?p=1_48
I bought it about 7 months ago, wear it all the time, and it's still very very poofy, hasn't died at all. I bought it in black, a friend of mine has it in white, and the lace on hers is much nicer, in case you were interested. The only problem with her white petticoat, is that it seems to have weak seams, and sometimes tears and has to be fixed. The one I got though, doesn't have that problem at all, the fabric is strong and doesn't feel like it could tear. I guess my friend got a faulty one...?
At any rate, my Classical Puppets petticoat is very good quality, has a huge amount of poof, and doesn't seem to be dying at all on me. It's not the same model as the one you're considering, but I just thought I'd let you know that I'm quite impressed with it.