KeyBoard, what handles good on KB will handle good on a wheel or game pad, but, what struggles with KB handles better with KB and mouse. I've notice with torq out the wazooh it is hard to keep a car on the road but, with analog no contest. I've been playing and modding with gta since gta 3, it uses one master file to houses all the vehicle's handing and characteristics, it is very clever system and more than just GTA uses such a system. it allows for each car to be fleshed... artistically with it's own character so to speak.
I love playing with such characteristics had i not lost some stuff through t years changing hard drives and computers. I had some sweet handling mods, gt3 through gta iv. in gta sa i had monster truck that could climb just about any hill or angle wall but, still handle real well. in gta iv i have a "bullet" which handles like crud on KB but, flies with a game pad, and i have "blista" the handles like dream and does 2 city block long burn out and is sweet on both kb and game pad.