DriveCrypt Plus and Dantz Retrospect b/up-a couple ?'s

I'am trialing the demo version of DCPP and really like it so far. I also use and like very much the backup sofware by Dantz Retrospect. With all my HD's encrypted how should I change my b/up plan which has been a full b/up every week to a removable 200GB HD? Should I encrypt the removable drive where my b/up set resides? As far as restores is there any considerations there with these two products, both of which I really like. Retrospect especially has proven itself and I'am proud to be a registered user of it. I will also be buying DCPP after a few more days of testing. Any advise on these two products and is there another better or comparable full disk encryption program out there before I drop $155 for DCPP? I thank you.