Honestly, I think folks should just let chdman do it's thing. Set it up in a bare bones system and forget about it.
Unless someone has stated officially that it may be flaky and I missed it?
I have only used it and have read and written hd's probably close to 50 times and have never had an experience that made me look elsewhere.
I won't be using the newer chdmans though, I'll stick with the last version that doesn't require flags(0.145?) and use the latest chdman to update the chd.
If that guy doing the chdman gui added a read/write HD function then I would probably use the latest.