monad thinking process

Greetings. I have very little experience with monads. However my first impression is that there is too much thinking process involved in programming with monads, and it is very time consuming, at least for a beginner like myself. I don't know how productivity changes once you get used to programming with them. Also, I have serious concerns about the maintenance of programs written in monadic style. Since there is too much plannning overhead, it doesn't seem suitable for evolutionary software development process. What do monad experts think? What do you think of code readability? How easy is it to prove that programs written with monads are correct? How does changing one function affect other functions, in terms of maintenance? Thanks