I realise that I'm a bit late to answer your question CanadianMaestro, but I read the responses that you got so far, and I share LC,s opinion 100%.
I see Grados as follows, the whole SR and RS series, all of wich are better suited for small scale recordings, the GS1000i, and PS1000, wich are my go to headphones for everything that's large scale, and the PS500, wich, with their strong bass bias, and slight treble roll off, have, what I consider to be, the most unGrado like sound.
I have owned the PS500 for about 2 weeks before switching to the PS1000. I understand that coming from me, this might surprise some of you, but I've held my peace long enough, Professionnal Series, the PS500?, more like Piece of Sh&t!!!, John Grado must've been on something good when he came up with these. I'm sorry if I'm stepping on some toes here,
but I simply can't take all the praising that SOME people have been giving them. In mi opinion the PS500 have more in common with Beats by DrDre's sound signature, I can't even say signature, it's more like a mark, a bit like a dog who pees on your leg to say that you're his, or in this case, that you've been had, I should say. I already feel better now that I don't have to keep up this Mr nice guy charade anymore regarding the PS500.
On a more positive note, I'd like to say to all the PS500 owners, including Focker, whom all the time I was writing the above comments, could hear sharpening his pencil, probably less to write a responce, and more to stab me with it, to disregard the above comments about his beloved (and rightly so) PS500. The force is strong with this one, the PS500 have a strong following. They are indeed a different flavor of Grado, but isn't variety, the spice of life?.