I doubt that you'll find an ISP with much better customer service. As far as I have experienced, that's where ISPs usually tend to save money ... by reducing the quality to a minimum. Either way, to me it seemed as if iWeb's customer service was pretty good actually. As far as pricing goes, a lot of those companies with "great" offers are pretty fishy, unreliable, unstable, lots of downtimes, and so on, so I wouldn't really trust any cheap offers. I think that, starting from September, it was just kinda a "hard time" for iWeb, or, as you may call it, bad luck. Nobody expects certain stuff like this to happen.
Besides, the first lag problems that occured in September had nothing to do with iWeb actually. It was some malware tool on the database server that drained extreme bandwidth, no idea how it got there, but we were able to locate and destroy it.