I've been biking to work for the last 3 years. It's still hard but enjoyable. In the morning I am really grumpy and I just want to stay in bed, not because I don't want go to work but just because it's so warm and nice there. I really hate mornings, all of them. But after i overcome all of the backlash from my body and actually ride everything started to get better. by the time i reach my work I'm almost ready to work. Bad weather is actually not that big deal but the need to get out of bed is.
It takes me roughly 30 minutes to bike, and it's really help me to wake up. Going by bus now feels so strange, slow and sleepy - you can't be delayed by 1 min otherwise bus will leave. That mental burden of constantly keeping timetable in mind for bus is noticeable.
There are downsides, obviously, but I try not to overspend on the bike and keep things simple. With purchase of a basket the bike became even more versatile.
I don't know if there any other benefits, these things we will see in years to come.