[boggsie]

Of course there are bugs.
If you want to know if the current problems will impact your usage patterns, follow some of the ROM threads where the 28xxx builds are being used and discussed. Chances are those folks aren't gong to wonder out here to see and respond to your question.
Personally, I haven't perceived a performance improvement in 6.5.3; it seems to be more directed towards visual "enhancements" to move to a even more finger/thumb friendly OS.

Best regards,
-boggsie