I do not recommend using mixin 0 unless you are an expert and prepared to handle the delays/issues (mixin 1 should probably not be used at all).
It looks like many people have problems withdrawing Aeon from HitBTC, and of course they don't have any choice in the mixin number, as it is up to HitBTC... Btw, if mixin 1 is not to be used, should it perhaps be disabled?
I also don't have any control over what software version they use. It can't really be fully disabled because there are some situations where your coins can't be spent at a higher mixin. Despite the possibility of delays and expired transactions at least you have a chance to recover your coins if you keep trying (and now can use the new fee multiplier option to push it through).