Geof, I've never tried winter sowing tomatoes but I was thinking that they probably wouldn't get going enough for us in the north... I guess we are just doing our own version of WS, by sowing them under lights!
Angie, I actually don't think it would matter when we WS'd the tomatoes, I think it would be okay to do so early in the winter because they reliably self-sow no matter what the weather, but they're just too late to have enough time to produce much of anything.
Claudia, I highly recommend trying Pruden's Purple, it's really an excellent variety!