Im buying a third-party USB keyboard and mouse, as quoted in the FAQ. I cannot afford the original keyboard and mouse because here in Brazil theyre extremely expansive. But some of these third-party sets have an indication: for both windows and MAC OS, and some dont. Does that mean that the ones without the indication will not work? Or it only means that these with the indication have been projected more properly? The equivalent keys quoted in the FAQ are not rare, on the contrary, they exist in any keyboard the one with the windows sign (equivalent to the apple sign) and the ALT command, equivalent to the optinons, right? Is there any other special care I should have when buying them?