It's simple. For really slow computer you need antiX. For eeePC I would go with antiX
If you have better computers and you have on all installed Mint, I suggest you replace one of the Mint with MX and see how it goes.
Mint is my first Linux love. I still like it. I probably always will. But there are no more Mint installs on my computers. Only antix/MX (on Debian side). Just sayin... ;-)
p.s.
Just got for 99$, (one of the slowest you can get) Chromebook for Black Friday. Perfect case for antiX. It would fly on it.
Fore some reason I can't get antiX on it. So I tried MX. Didn't expect much. Surprisingly, MX works quite well, I'm impressed.
If your other computers are fast enough for Mint, MX should fly on those.