I had a DL4 and an RV-3. I liked them. With DL-4, maraming options, and you can store a few settings. RV-3 naman, the combination of the reverb and delay is amazing.
I put these away after getting a DM-2. The sound is just more natural to me, eventhough the delay time is pretty damn short (about 300 ms?), the weird crazy oscillations definitely make up for it.