I've done a bunch of 8051 projects, if you have to choose between ARM and 8051 - choose ARM! 8051 cores are cheap but they have weird memory hierarchies - mana

I've done a bunch of 8051 projects, if you have to choose between ARM and 8051 - choose ARM! 8051 cores are cheap but they have weird memory hierarchies - managing them results in giant code, unless you're willing to break into assembly way too often