I don't know beans about the S2, but have heard the same horror stories. I used a Quantum Radio Slave for several years when shooting film and continued to use it after getting my Canon 10D. It works great with my ancient Novatrons, it just doesn't miss, whether line of sight or not, with the added advantage of batteries lasting forever and a day. I have not used it yet, but picked up a little gizmo, I guess a voltage regulator to go on the hot shoe if I need to use a pc cord to fire the flashes. That supposedly prevents any damage.
My place