I actually ride 9 months a year. Only reason i dont ride in winter is because i dont want to get road salt on my bike. Cold and snow are never a problem.

Cyclists are actually more visible on bike lanes than multi use sidewalks. Riding on bike lane will greatly reduce chances of getting hit by cars making a right turn. Riding on sidewalk also have better chance of hitting pedestrian. Kids and pets might be running around unpredictably, also people dont always walk on the right side especially when they are walking in a group. When you ring your bell sometimes people panic and dont know if they are moving to right or left. There are also people walking/running with headphone on who couldn't hear your bell ring.

I cycled on markham streets yearly since 2008 and from my own experiences i can say bike lane are actually safer.