WHMCS + LiveZilla = Total Win.
Seriously, HostBill's livesupport is nothing compared to LiveZilla, which is free, and WHMCS is really solid, not only it IS solid, it also feels well scripted
WHMCS is the best billing and support system to use
WHCMS is the most known and from what I know it's more stable, bug free and more secure than any other.
If I would have to choose between the two, I would give it a go to WHCMS.
I haven't experienced a single bug in HostBill, so you're kind of talking out of your --- there.
There have been bugs, but Hostbill is very fast at getting out the fix and adding it to the version that it effects. But Hostbill staff's attitude is disgusting.
I use WHMCS U have a lot of options and vety easy to use ,