Tomlee59 made the point, above, that the dead iMacs in his possession were in his possession because they were dead. Your experience at an AASP is similar, in that you would not have seen the iMacs coming into the shop unless they were dead. A highly skewed sample, from which you extravagantly claim that all iMac slotloaders are crap. What about all the slotloading iMacs that you have never seen because they just chugged along, in the Queensland sun or no? In the iMacs' home country there are many places with summer temperatures that would leave all of Queensland but Mt Isa in the shade (metaphorically).
My skewed sample, above, of four slotloaders (I didn't even mention another two that I have, also trouble-free) that have been meticulously maintained and deliberately set up to promote ventilation, has been fault-free in the Sydney sun. I'm not convinced that the ingoing air temperature in Qld is so different from that in NSW (8.5° latitude difference) as to impel all—or even most—slotloaders in Qld to self-immolate. I should have preferred forced ventilation in my iMacs, certainly, had the choice been there. Consider though that when the Summer 2000 iMacs arrived they were the ant's pants of the time, however passé they may be considered by some to be now, and if you wanted their capabilities you accepted their disadvantages.
Your trayloader, by your own account, has had a much more varied, inventive and chequered history, its fan notwithstanding.
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