I wouldn't run 19"s at all, I don't think the ride quality is worth the look. Not to mention you're more likely to bend the rims when you hit a pothole.
I'd go with the 313's in 18" for summer and some beater 17" wheels for winter. 18" wheels are awfully big for snow tires.
Also keep in mind that the 19" 313's go for $3800, so they are actually a more expensive wheel than BBS's.