Fantastic replies, everyone... I got the rc20 a long time ago, it was great on a gig doing Floyd's Wish You Were Here, I can't remember if i preloaded that 8 or 16 bar finger picking intro thing that I then did the solo over, my 3 friends at the gig were impressed...
The problem with that model was that I had to be exact on the loop timing end, which pretty much killed the idea of using it for live recorded looping, but nice that it ran on batteries, the comp click track sucked and no foot control of it.
A while later I got the jamman becuase it has "loop stitch" which is the timing quantizing / measure compensation and might go by another name also depending on the manufacturer. Requires a wall wart and once again, no foot control of the comp click "rhythm" track thing which is essential to me to live record a loop track accurately, yet I still need the quantize/stitch/compensate, because i refuse to have a glitch in the timing, it annoys the hell out of me and I'm a bit of a perfectionist, I have a feeling that even if the audeience doesn't know what's wrong, they can feel it and I would know it so it would be a fail for me....
Ok so now more friggin YEARS go by, and I find that the Jamman Stereo has a jack on the back that has the rhythm track able to be spit off the main when plugged in so this pretty much checks off another box for me, but of course not the battery issue.
So for the control of the rhythm track I use an old 2 channel volume control that I got for guitar volume on foot rather on the pinky if you have a strat, I saw someone use that for something cool, like fading up the level from zero as you unbend a string and other sutff.... So then I used a Roland multi-channel keyboard amp I already had for a mini-pa and I use a spare channel to pot up and down on the click/rhythm/comp track for timing coming out of the jamman stereo, this works well since I'm using this for my acoustic and the keyboard amp helps with the fuller sound rather than a guitar amp.
I turne down a lot and I can't deal with the potential for preloaded loops not being in tune with my current guitar tuning even if i am using a tuner, yes, most of the time it's fine, but having to remember what tuning I used and stuff and what number loop i have stored, etc., it's too much when live, i have enuf to worry about with mixing, levels, feedback prevention, etc., etc.
All this is fine if it's my gig, but one last thing I'd like to do is go to an open mic and just drop a battery operated looper down and I don't need a click track, but I do need tap on foot control and loop stitch, I can't seem to find this combination of features.
The amount of looping I use is minimal so it's funny how much effort I put into it, but it really helps me with my confidence in my sound and timing and I really just use it for a bassline, or a small comp part, or not at all, it's subltle and probably more for my own peace of mind, but when I do use it, it adds something massive to the sound, even without any additional layering, i can solo and it frees me up and lets me jam even if only for adding a minute to a song, if you add up ten of those that's a good chunk of time at a gig if you know what I mean, how much work we have to do finding covers we can do without making us ill from coving them.
And if it's an original song, then I can do whatever I want to it without ruining it for anyone. If it's an open mic, I can't bring a bunch of gear down, and I really want the ability to chill w/ the features I friggin need....