A lot of strange comments here (OP included - but it doesn't matter now what he should have done before purchase, so I won't dwell on it or beat him up over it). OP, what's your specific problem with these tires? How to you typically drive your car?
How many of you have personally driven in the cold or on ice with different tires? I've driven on summer tires in the teens, with a very small amount of slush, and I was surprised at how well they handled (I had just purchased the STI from a dealer in NH and fully expected to be sliding all over the road during my drive home, based on what I had read online.) I did take it easy and was extremely careful; I don't think I exceeded the speed limit the entire time. I thought I'd save some money and chose to swap them for agressive, albeit relatively cheap high-performance Toyo AS tires that were absolutely horrendous in the snow, even with three limited-slip diff's! I finally settled on a dedicated set of winter and summer tires, which were really, really awesome.
I don't have and don't plan to run a summer tire on my Forester XT. The Premier A/S's perform ADEQUATELY, are much better as a touring tire (summer tires are freaking loud, especially near EOL), and last much longer than a summer-only tire. This thing hauls, but it's a freaking CUV on steroids. A summer tire would be great, but it's simply not necessary for a souped-up Forester. Is the MK-Z really a sports car...or is it a luxury car with a powerful engine? Does the distinction matter?