It is recommended to have the same tires at all the wheels. Tire Rack for example won't sell you a pair unless they confirm you have a matching pair already. I had different pairs for a week, blizzaks on the rear and all season on the fronts. The handling was OK but sometimes the steering wheel didn't respond because the front tires weren't gripping properly. But that's just here, no snow in Cali so you don't have to worry about that hehe.
If anyone is intrerested, I have a set of all-season tires that I only used for a week before I had gotten the blizzaks. I'm not sure what their brand is, I will find out soon and take some pics. I got them for around $600 and they are just sitting there now. I won't switch to them in the summer, I'll just stick with my snows all year long. Email me if interested
yallough@twcny.rr.com . I'm letting them go cheap.