Let's just say that when I make a dedicated linux installation I expect to be able to use filesystem of my choice and (software) RAID solution of my choice without running into all sorts of crazy issues. I could not care less about the people who play with fire and install Linux on the same harddisk with some operating system, although I realize that it is an important use case for some people. I just think harddisks are cheap and worth the investment to avoid the need to deal with this fundamentally risky configuration where multiple operating systems are expected to cooperate one way or other.
My personal experience with GRUB has been one of long frustration because it has taken so long before it started to work properly. But hey! It wasn't a .0 release before either, so maybe I was wrong to expect it to just work. Then again, I heard a wise man say "optimism kills". I expect to run into trouble as soon as I deviate one bit from what the average person is doing.