If it's 'not recommended' and you have an accident you might find that you are uninsured. It's not about snow it's about ice too. MG4s are RWD. If you have the rear wheels 'pushing' you into a corner and the front wheels lose grip no amount of extra grip at the rear is going to help you. I live in the North East, we have snow every year and I have a set of winter wheels I put on at the end of October every year. When I had a Saab 9-3 I could get up snowy hills that 4x4s (with normal tyres) couldn't get up. My driving instructor told me (50 years ago) 'no slower than 20 - no faster than 30'