For serious daily Knoppix use, a good persistent store is mandatory, and that means >2 GB for me. Just upgrading/book-keeping stuff easily reaches 1 GB, and I normally go for 4 GB at once. The CD is stripped down, to the point that something important for some uses is usually lacking, therefore, I start with the DVD version whenever I can. Total system size therefore becomes ca 8 GB. But that also means I can't place the remastered version on a CD/DVD. And why should I?

I run Knoppix from internal HDD, USB HDD, (fast) memory sticks, SD cards, smartphone - seldom CD/DVD. These have the space I need, and the KNOPPIX directory (including persistent store(s)) is easily copied.

Booting? Thus far, I still prefer legacy GRUB (not the "new" thing) installed on its own partition, where I can add boot alternatives just by adding kernels and initrds and editing /boot/grub/menu.lst. Only limitation is with Win7 - I don't need it enough to chase the workarounds needed to Linux boot it, relying instead on virtual machines. I may turn to GRUB4DOS later.