I bought a pair of Aviator's last summer and having never really worn shades in my life, haven't stopped wearing mine when the sun is out.
Mine are a variant of the traditional style with wider plastic arms rather than the thin metal as they suit my baldy head/face better. Go for the polarised len's as well, its like giving your eyes a bath on a bright summers day....A bit of a weird explanation
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but go and try some and you'll see what I mean.
I ended up paying full price for them at the sunglasses hut at around £180 (but did get my wife a free pair of decent DKNY shades too - which had been up at £100)
Its not worth shelling money out on ebay just in case they are fakes imo