This thread covers the differences pretty well. I'd add that both are very good bikes. It's gonna come down to which one you think is more comfortable and how small you need it to fold.
I get my D3 on NJ Transit during peak hours with no problem, but the Mini fits on an overhead luggage rack, and the Curve will not.
Originally Posted by
invisiblehand
I think that the Mini is a great machine except that it isn't particularly good at carrying stuff since most mounted racks would interfere with the fold. You can get a nashbar front rack with the 15-pound capacity on the front fork and fold the bike.
I use a backpack. I don't think any folder is all that good at hauling stuff, since it would more likely than not interfere with the fold. Folders with suspension (it seems like that's almost all of them) can also be tricky to put aftermarket racks on. I think the Mini needs some mods to take a rack.
Does anyone ride a folding touring bike?