I love my recumbents but I hate to ride them on slippery surfaces such as mud, loose sand/gravel or maybe even snow. Mainly because of the balance. I had two crashes on mud patches because I saw them too late and was not able to stabilize with my legs in time. On an upright bike you can use your legs as counter weight if you start sliding. At least to a certain degree. And with a straight stretched leg on an upright bike you have a better chance and more strength than with a bent leg on a recumbent. Fortunately we don't have snow where I live now. And I avoid gravel where I can and try to ride on pavement only. I really only ride recumbents because of my back problems. They work much better for my back than any upright bike. I am not doing it for speed. Just for comfort. And if we would have snow here in winter I would get a trike for winter to be saver on three wheels.