Hi there,
I own a Big Ben Gametab One (a rebrand of an Ipega Android handheld) and I think it is okay. But the firmware really is extremely slow and bloated.
Big Ben never released their source code or opened it for custom development as far as I know. Aside from installing custom firmware on my old Xperia S a few years ago I have no experience in custom ROMs whatsoever especially not in making one myself.
But I am making a vocational training as a software developer. So therefore I would like to know how hard is it to make my own leightweight custom ROM for such a device myself. I mean there so many Custom ROMs on XDA Developpers and if I can rely on other custom ROMs for similar chipsets is it possible to realize this without a huge amount of effort?