I've tried a few times and fell off every time so now I don't bother
Depends on how fresh the snow is and whether it is icy or not underneath. Even one time when I was doing well following the wheel tracks I ended up falling off at 1mph on a patch of black ice with no warning.
If you are going to try I would say:
- Bike choice is key. Something with big knobbly tyres or studs is a good idea. Mudguards or limited clearance to the frame is bad because the snow will build up and jam your wheels stuck
- Ditch the cleats and wear normal shoes. Cleats just end up getting full of ice when you walk and don't work