Their product is actually good, the problem is their customer service.
If you have to contact them, they are willing and helpful, until something doesn't go right.
I had a reseller account with them for years and they never accepted that I could not login to it. Every time I wished to they had to send me a new password through email. The recover password simply didn't work.
Eventually I'd had enough and left. They agreed to do a backup of my database, but they botched it and it had to be rebuilt later.
They also agreed to transfer a domain to another host. They did not do this (and I hve now lost that domain) and 8 months later said my acccount had not been cancelled as I did not inform them through their ticketing system (I had) and they were advising a collection agency to collect another years fees!!!
Months of emails have failed to achieve anything, my anger levels are unbelievable.
I would warn anyone to think twice before considering heart as their host.