I'm a client myself and have had a fair share of issues since things when from Haste to Centex and even told the OP I was done via email and was moving to another hosting service.
I didn't at the time as I got tied up and he went hard to make sure I was satisfied.
There was an issue I was not even aware of as I was not getting emails to one of my accounts and a client called me on the phone to let me know she was sending emails and they were bouncing.
I put in a support ticket and after a little back and forth it got resolved.
I'm not moving my sites; I was going to but I see that the OP's team is working hard to iron out some of the bumps in the road that I've encountered. Sure, it cost me clients and money to stay with him but I think it is a smart business move to stay with a company that has traditionally had a solid track record that has only recently had issues.
Everyone has problems in their business and stuff happens.
Everyone.
Looking at the long term track record makes a lot more sense than a knee jerk reaction of moving from host A to host B in my opinion.
Do what you think if best for your sites/business,
@lifemega, but as a person who has been in business for a year or two it makes sense to me to go through some of the growing pains with the provider than rolling the dice on another one.