There's nothing wrong with the Hydrasynth's keyboard that I know of. But then, "that I know of"...which is important because the reason I don't have one is because I had a particularly nasty encounter with one of ASM's US reps when I dared to ask when I could expect to get the one I'd paid for at Sweetwater three months previous. I immediately changed my order there to an Argon8 after that; I'm NOT going to deal with companies that have Type-A asshats as their user base contacts! I did get to futz with one some time back and I thought the keyboard feel was nice, but I still missed the CS-80's weighting and tab controls to mess with the keyboard response on the fly. Even so, I'd pulled the trigger on one...only to have to go and catch that bullet myself after dealing with ASM and re-aim it toward Modal (who, I should note, DO know how to behave themselves, answer user questions, and the like).
The only thing worse than having a bad implementation of some feature is having to deal with a company that offers you the "experience" of getting verbally punched in the face. I don't give a flying about how amazing the Hydrasynth is, therefore...I'd rather deal with a company that doesn't match their customers up with dysfunctional, screechy people after having dealt with people who have no idea what you're talking about due to the language barriers.