When I started putting together a pedal board, I had several delays I absolutely wanted to have.  I wanted a garden variety digital delay, an analog tape delay, and delay with modulation and a BOSS delay that could deliver the classic "bucket brigade" delay.  After I finished my list I realized I needed a HUGE pedal board and a larger budget.  Then I discovered the DL4.  I played with one for a bit at a local retailer and then purchased one.  The unit is great.  There are a number of presets that more than covered my needs and for each preset you can customize your sound giving you virtually unlimited options for delay.  There are 4 buttons, 3 of which can be used to store either presets or customized settings.  You can switch between the settings on the fly with ease and not degradation in sound.  The lone drawback, but for me not enough to dissuade me from the unit, is that the 4th button offers a short loop option, but Ive never used this as I have a separate looper.