Honestly, Forza (and daily driving a 73 mustang) really taught me how to control skids, and regain control in emergency situations, that's why I bought the wheel. I think you said you always use tcs and stm.. turn them off and get used to it! I would go to a nice open parking lot when it snows, and just get comfortable with the car, theres no better way to learn. If you can control the car to the point where you won't lose it you'll be fine. A driver mod is the best way to improve on any car , tires are usually second and more expensive.