I don't think it's worth it really! If you're worried, try a skid correction course for less the price than a set of tyres you'd rarely use! I've been on one, and a proper skidpan course, and it makes you more confident and teaches you a thing or two! Also interesting to see how FWD and RWD cope in the same conditions! I'm fine in snow, I just worry about other drivers hitting me so spend more time focusing on what's behind me, making sure their not to close.
Infact due to it, I don't think I couldn't of saved Fi's car last year in the icy conditions! Imagine a stock 106 on 4 different 13" budget tyres with no tread, and cracking on the sidewalls there so old

I was pretty calm when I was facing the nearside kerb at a feeble 10ish-mpg, whilst halfway through a left hand declining bend

She didn't find it funny though.

I still needed two corrections as my first one was a tad zealous!
Bearing in mind even just 10mph can be deadly in the snow
