I started using a small MUP that runs about half a mile near the end of my 12 mile route. I'll have to say it's a very bad idea and I'm not going to do it anymore.
It's an MUP or paved path parallel to the road, not connected to it.
1. Cars pull up to the road and never pay much attention to MUPs. At least when I'm on the road cars have to stop at signs/lights. No such love for MUPs as most drivers don't even consider them. A great way to get smashed by side road warriors.
2. ****. Dog ****, branches, glass.....lots of **** all over the things. At least on the road cars are constantly "cleaning" the road for you.
3. Peds with dogs. They are always in the way and have no idea you're behind them. Why get in each others way?
I just don't see any reason to use an MUP. They seem dangerous and dirty to me.