Welcome chunkYE! To play it safe, could your parents actually do the ordering of the other speaker....OR....as I'm not sure how the Aussie import law works, they say that they combine the items and if it exceeds $1000 you have to pay duty, but what would happen if you ordered 1 x M80 then waited a week or two, then ordered the other one? maybe you could get your parents to order the other one a week or two later to be DOUBLE safe!
Re the GX5, there are numerous articles on the internet reg the fan noise on Pro Amps(usually for home use). They usually involve swapping out the fan for a quieter unit, or slowing the existing fan down with a resistor. People say it's pretty straight forward. You have to keep in mind that the fan may hardly ever come on in the less demanding home setting vs what the amp was actually designed for, and chances are, if the fan engages while you are playing music this loud, you'd doubtfully hear the fan anyway. 'Zimm' who periodically drops in, uses a GX3 on his system I recall, and I don't believe he felt it necessary to swap out the fan on his unit. People say you would only hear the fan at very low volumes, but at low volumes you have to wonder if the fan would even engage.
Hope some of that helps.
