Areas of this road vary from pot-holed sections of gravel strewn pavement to nice stretches between the little inhabited sections that randomly appear out of either jungle or along side fields with any sort of crop dependent upon time of year.
There are more interesting rides from north to south across the mountains IMHO.
FWIW, I would recommend the mafungo in Humacao at the bar down by the waterside. There are two bars side by side at the bottom of the hill as you enter town from the northwest. The fish is good at both. Plan to stay for several hours of afternoon beer starting at 2PM with all the locals. Sorry, I don't remember the name, but I do remember the food and inexpensive beer.
Edit: I found one pic of the back of the building, here it is.