Been there... done that... It is good for generic sets, but it does take some of the dynamics away from a live set.
I have used it's evil twin the Roland PMA-5 for a live show, well actually 2. The PMA-5 can hold 20 songs. I would have one song be whatever I was playing, then the next song be just the vamp or the groove. That way if the audience really like what was going on I could continue the groove for a while.
After the 10 songs was over, I would go to the other PMA-5, then load the next set list up into both during the break.
I like playing with a live band much better.