I'm not sure I buy all the arguments on here about these all-in-one systems taking out all the fun of brewing. I've been considering moving from my 3-tier system to a Grainfather recently and it seems like a very attractive alternative. With the Grainfather I would still crush the grains, mash, sparge, boil, etc. The way I see it, the only thing I'm really losing is the process of transferring liquid from one vessel to another and fiddling around with temperatures. To be honest, those two things are what I enjoy the least anyway. I'm getting very tired of having to thaw my pumps and lines with a hair dryer in the middle of the winter

Other than the obvious high price tag, I don't see many downsides to it.