Has anybody here tried the Manfrotto 521PFI iris/focus controller with the HMC40? Does it work well? I just bought the Varizoom equivalent but I'm going to return it because it's flimsy and way too sensitive.
The 521 works fine with the HMC40. But your comment about flimsy and too sensitive will hold true for all controllers of this type, though I think the 521 is the best of the bunch. There is just a limit on the sensitivity on electronic controls of this type. It also has a limiter arrangement so you can do repeatable focus which is very cool.