I don't know what to tell you about that one. I myself ran v5.0 for several weeks without issue as have many others. I remember some ROMs for some reason unknown to anyone just seemed to not like your phone, as you said, for lack of a better way to put it.
Anyway, did you miss the beta posting? I know this is not your primary phone and so you wouldn't have a ton of time to test which is why I just put the beta up in the thread for whoever was willing. I would say the beta is stable, save the two issues I mentioned in that post. I've posted a fix for the RSS Tab and the other one is not really an issue as it is a difference.
Anyway, to any of you who have downloaded the beta and been it running for a day, some feedback of any sort would be greatly appreciated!