About the cell phone interference...
Sometimes, at 3-day outdoor festivals I don't use my SBM1 because it would simply need too many batteries which I don't want to carry all day. I found that when I don't use the SBM1, almost all of my recordings have cell phone interference at one or more spots. However, I've never had any problems *with* the SBM1. So, my guess is that the interference happens during the A/D conversion.
Another funny thing: I just came back from a festival in Belgium and during a show, you could clearly hear some cell phone interference over the PA. Seems like portable DATs are not the only devices that have problems with it