I can't speak for the HD497 or the PX100, but I think that the HD212 are the worst headphones over 20 UK pounds that I've ever come across. And 90% of the phones I've had fall into that category. A fizzy cheap treble, and far too much bass. A terrible combination. Comfort wise, they weren't bad, better than Grados, although if you do find them constricting some careful coaxing is required of the one piece plastic headband. But mainly just fitting the headband close to your head reduces the leverage and reduces the pressing (common sense really) feeling.
Although I still didn't like them that much, the PX200 sounded a lot better.
Grados. The SR60 is functionally impractical for portable use. The SR60 is not durable, it's fully open, it doesn't work very well with low-power sources...Over-bright from most portable sources and can't develop anywhere near a decent low end. Up the volume to compensate for the slightest ambient noise and the SR60 will clip from a portable, as well as annoy anyone near you. Personally, I don't believe the words 'Grado' and 'Portable' have anything to do with each other. It makes my jaw drop to see magazines heartily recommend them for that very use.
I would say the PX200 is the best phone out of what you've listed for portable use. They're practical, surprisingly well closed, quite stylish, very portable and it's not as bad as the HD212.