Been reading all the old threads, figured I'd just ask again for an opinion. 1) Is a looper really that great for improving? What are some good exercises I can do with a looper? 2) What's the simplest one to use for practice? The choices as I understand it are: *Line 6 DL4 - Easiest to use, as it has 4 separate buttons for looping. 23 seconds. Maybe slightly older technology now. Is 23 seconds enough? *Akai Headrush 2 - 23 seconds of looping, slightly shorter amount of time for overdubbing, probably one of the easier ones to use after the DL4. Easy to use live. *Stereo Memory Man w/ Hazarai - 30 seconds of looping, maybe kind of annoying because you have to hold the record button down. *Boss RC-20XL - Long record time, same functionality as the RC-2. Has more pedals, so probably easier to use. *Digitech Jamman - Long record time, has a lot of presets. *Boss RC-2 - Long record time, kind of annoying to use live as you have to do some kind of double-tap to stop recording.