I just ordered The Count for Carcassonne. We usually play using River I, I&C, and T&B. I'm not sure yet how often we'll use the count, although I'm sure we'll give it a try. Mostly I ordered the expansion for the alternate starting configuration offered by the tiles. I noticed in one of the reviews that The Count expansion can be used together with the River. Question: Do you just begin the river adjacent to any field edge of the starting Count tiles? How well does this work, in your experience, and how does it affect play?
Yes, you can use them together. You just pick a legal place to start the river and work from there. You just need to follow the no immediate u-turn rule and keep it from hitting the city.