Not many can give you a definite answer about which amps will synergise well with the PS1000 because of the simple fact that not enough people have them yet.
Assuming PS1000 is as picky with system pairing as GS1000, option A might be a hit or miss thing. If the PS1000 likes (or is at least decently listenable with) your DA220+Move (I'm assuming this is the portable amp you're going to use) then good for you. If not, you basically have a high end headphone collecting dust until you find an amp that will make it sing.
Option B would be slightly safer, and you can try the headphones/amps/pairing that you are interested in. Money spent would be safer I guess, and if you buy used your dollar will go even further. Don't think any PS1000 will come on the FS forums anytime soon.

Well, the bad thing about this is, you won't be owning the current in-production top of the line Grado can if that bothers you.
Personally, even though I've not heard the PS1000 (well, few have) I would go for option B easily. I've had enough bad experiences of buying things that I've not tried.
Of course, you
could just wait for the PS1000 to be released and see if they were worth the hype (to you of course).
I've not heard the PS1000 so my opinion might mean nought, but hope this helps.