Hosts are not unreliable, it is the people hosting their website of the same server as you that you cannot trust. Most problems that cause your site to go down is a bad script that someone writes for their website and it causes processes on the server to freeze up which in turn hurts everyone's site on the server. The cheapest way to get around this is with a VPS server so that other people's scripts do not impact the reliability of your site. You can get good cheap VPS Hosting at
http://www.virtuosonetsolutions.com/...iate.php?id=46