the original is the bamboo inner, and a cotton-topped pul outer shell. They had 2 versions of this. The first had 2 laundry tabs, the more recent has only one. People were having leak issues with the first version I believe, but that hasn't been a problem for us in the second version. The first version was also when they were "Modern Baby" instead of Close Parent so the label on the older ones will say Modern Baby. Just something to look out for if you are thinking of getting some secondhand. You won't see this nappy called "dream dri", it'll just be the Pop-in Bamboo
The put out the dream dri (v2) version last year. It has the same outer, and a microfibre inner. Very quick to dry!! (big bonus) And actually for us it lasts as long as a bamboo, which I was surprised by.
The new dream dri (v3) is very nice! They've taken the cotton off of the outer, and replaced the microfibre inner with minky, though it has a stay-dry layer on top. It's made the nappy slimmer and they say more absorbent (again, they all work fine for us so can't verify this one!) and the only negative is that they upped the price
Their website still says microfibre for the dream dri, but it's the new v3 one as they've upped the price from the old one. They need to update that! You might find some v2 dream dri on sale on some websites, but I think most places only had the pumpkin colour left as they stopped distributing the v2 to make room for the v3.
I posted some pics of the new dream dri when it first came out, will find the thread and put link on here for you. I really like it!