I'm currently running KitKat on my TassVe, which is essentially a Totoro under a Galaxy Mini shell, and I can say that it's smooth most of the time. Typing can be a bit laggy, and some apps (such as Titanium Backup) can take a long time to boot. But overall still smooth enough for daily use. Only complaint is the epic power consumption of the ROM.
Oh and this is the experimental build. Before asking, no, I will not provide links to it.