I’m very impressed with eurofficial.com
Branko Kotur is superb in terms of customer support and he has no problems with gambling portals as should no one have.
I’m hosting several websites with them since almost 2 years and I don’t remember of any noticeable downtime.
I have been trying hosting providers for more than 7 years and I had very bad times with some of them. This one is very good. If you want to host more than one domain, choose a reseller plan.
You can also check http://www.webhostingtalk.com
There are several offers around there, and you can check for hosting reliability.