I was a died-in-the-wool toe clip user, then switched to SPD, on all bikes, mountain, commuter, roadie. I've since started mountain biking on some really technical trails and I had to dump SPD after two bad falls that would have been prevented had I not been clipped in. The situation where the front wheel gets cranked to one side or the other without any warning will throw me down if I'm clipped in. Since I went to platforms I've saved myself several times in circumstances that would have been a crash if I was clipped in.

Having said all of that, I ride on the road clipped in almost all the time if I'm wearing SPD shoes. If there's icing conditions I just unclip and use the other side of my Shimano PD-324s