I bought a pair of PX100s for the wife at Audiophile in Atterbury Value Mart, Pretoria. so they may help you there... they are quite nice and laid back and natural sounding, can listen for hours... folding up is great! We are running around a bit prepping for the baby so would normally offer a listen, but things are a bit hectic...
I heard the iGrado's briefly and ito quality, they were perhaps a better match for the px100, than the SR 60's seem to be? not as foldable though and quite lively and detailed - compared to PX100, which may be your cuppa tea, or not, and didn't really sound like they needed anymore power than the iphone supplied, may well do better but was quite an eyeopener for ca. R500? Don't know where you can listen to it...
Also look at Koss Porta Pro, old school headphones that look quite 70's, coz they are and also about R500 on the web. iGrado's look very nice...
iGrado probably the reason I'd get a portable music source... even high bit mp3 sounded cool.
P.S. Am not a headphone listener usually so could not possibly say how good these are in relation to other headphones out there.