About the snow, they prob suck in the snow, the wider your tire is, the less traction you will have, because you tire will have less weight per square inch, because there is more tire on the road. For mud, wider is better; for snow, narrow is better. The only thing that might possibly increase your ability to drive in snow with those tires is that the actual diameter is larger than stock, so you will have less torque at low RPM's, making it a little harder for your wheels to spin. If you are concerned about snow, I'd stay away from the 225's.
