I can't say they are really bad since I use their other extensions for some clients using their accounts (I encourage them to buy for themselves for long term support). Then I tried their easysocial profile, and I did report that their plugin doesn't work with usernames with numbers. 48 hours have passed and still no reply.
Sorry for the late support as it is the holiday period here. All support tickets have been responded now.
This is one of the best plugin/component/module you can have for your money! 5 stars for the software, 6 stars for the developer (Tuan). All I can say is support is great, software is great, everything is great!