Can anyone tell me (in a nutshell) whether it's better than WinUAE
It has totally different concept to UAE, so comparing them is quite pointless IMO. Amithlon is ever further away from AROS, so comparing to it is ever more pointless.
why it doesn't seem to be developed any more?
amithlon_statement.txtHowever, AFAIK there are still some kernel upgrades for Amithlon being made (linux kernel upgrades adding more driver support, the amithlon itself is dead).