I'm with Karyn ... as long as you can swing the $, go for DE. I've used classic years 3 and 4, redesigned (print) year 1 and now using year 2 DE. The classic years were great and I was able to substitute other titles from the library when they didn't have the suggested titles. Even so, once I used redesigned for the first time last year, I felt like a whole new world opened for us. It was clearer, easier to use, included dialectic discussion guides, and would stay current as books go out of print. I knew I'd upgrade to redesigned when I came around to years 3 and 4 again -- then DE happened.
Since I needed year 2 anyhow, I got it in DE. I'm sold ... hook, line, and sinker. It's the same content and general organization as redesigned but so much easier to flip around. I'm sure I have "binder-strain" from hauling my big binders around, on and off shelves, pulling the current week out and putting it into a little binder to stash in my bag, etc.
DE is cool! (Have you seen the new features they're rolling out this fall for DE? WAAAAAAY COOL!) Having said that, I don't know if I will upgrade to DE from my year 1 redesigned. I can't justify it now. Who knows what the future will bring. However, I did upgrade my classic year 3 to DE already. I sold my classic year 4 so will buy DE when the time comes.
Bottom Line: I strongly recommend upgrading from classic to either redesigned or DE. It's well worth it. The jury is out on "upgrading" from redesigned to DE.
Shalom,
Monica