My city (
Novi Sad, Serbia, Former-Yugoslavia, Europe, 3rd rock from the Sun...

) has lots of separate bicycle roads. It is a great thing for begginner cyclists. However, intersections of those lanes over roads is a very dangerous place. Most were well designed, but in the last few decades, it has all gone to hell - no planning. So now we have newspaper stands with windows opening over a bicycle road. Caffee "gardens" taking 90% of the sidewalk, so pedestrians use the bike-road for walking. Large boards with advertisments just before an intersection of bicycle road and the car roads - so the view is blocked both ways. I prefer using the road (even though the law says to use bike lane/road whenever it is available).
Still, for begginner cyclists, it's a good place.
Bike lane on a car-road? We have a few, with car parking next to the lane often. Guess it's still safer for inexperienced cyclists than just riding on the road though.
Here's what a good design with a bad implementation (law enforcement and planning) looks like (not my video):
Volume 2
I had read some studies that conclude that more bike lanes/paths usually result in more people riding bicycles - which results in motorists being more used to bikes, resulting in cyclists being a bit safer.