I know a few locals with PAL AES systems who insist 50Hz is OK. Bunch of nutters.
As far as recall, you can convert it to 60hz, just by cutting the wire on one resistor on the PCB. But I can understand that some people might not want to do that to a mint Euro AES (that hasn't been messed with internally).
The few AES consoles that were privately imported to Australia were mostly the Euro AES, with 50Hz and English language.
For the rare handful of games in the 90s which were PAL optimised it was arguably better (better resolution at the same speed as NTSC). Those games where few and far between though.
For some games, like SF2 on SNES, they used workarounds that made the black bars not so bad. And on SF2 Turbo you could just select a faster game speed.
But, of course, game design back then was dominated by what the Japanese and American markets wanted, which was 60Hz.