My wife had a LOT of TMS treatments, and I read up on everything in advance and spoke at length with pracitioners and a manufacturer rep. The risk of seizure is really quite small, at least for the primary targeted region for depressoin (left dorsalateral prefontal cortex).

I haven't followed the technology since late 2009, but they were developing a unit for deeper penetration, and the risk of seizure was much greater--which was hampering development. But...maybe the units are now available.

Again, I think the evidence for pain efficacy is stronger for tDCS than rTMS, and at a minute fraction of the cost.