Hey matttttttt,
I can give you some advice regarding the etys vs. the grado 325. (not quite what you were asking for, but might help)
Basically, where the grados shine is in their midrange. It's magical. For small ensembles. Solo instrumental work. Vocals. Anything orchestral or with more complexity than a few layers of music, and the grados start to show their weakness. They're a little slow and mushy and show their imbalance.
The highs are harsh, and too forward for my tastes. Bright. At first I thought it was the amp, but no...it was the cans.
The bass is reasonably deep, and has good impact at high volumes. It's detailed, although a little slow and can get in the way of the other frequencies in bass-heavy music.
Overall, the grados are impressive upon first listen -- very involving and dynamic. A big "wow" factor. Yet after awhile, their weaknesses started to grow on me. And grow. They are by no means bad headphones -- there are simply better choices out there. Now, the RS-1's could be completely different -- retain the signature grado sound, yet not have the weaknesses of the 325s. I don't know. I don't like to make assumptions about headphones I've never listened to. For their price, the RS-1s should be a significant improvement over the 325s.
Now, the etys are in a whole nother ballpark. But they need power. Lots of power. Don't think you'll get close to the full benefit of the etys by using the jack out of a pcdp. The grados are great in that they sound close to their best out of a low-powered source. When powered correctly, the etys will have a brilliant bass response. As deep as you can hear. And you can hear everything in the bass. No blobs or 1-note bass at all. You don't feel the bass on your outer ear like the grados, but that's due to design. You still feel it inside your ear, which is pretty incredible for such itty bitty headphones.
The details with the etys are astonishing -- like taking a microscope to the music. Everything is extracted, making the listening experience just about as involving as headphones can get. Everything sounds soooo realistic and right. Highs are sparkling and crystal clear -- not fatiguing, yet not rolled off either. I can hear no roll-off, despite what others say. Maybe their hearing is better than mine. Again, it takes lots of power to get the sparkling, pristine highs, otherwise it will sound rolled off.
The isolation I need not mention -- I'm sure you already know that if someone snaps a finger in front of you while you're listening, you won't hear a thing.
Basically, I find the etys to head and shoulders above the grados (SR-325). I have found them better than any speaker I have listened to.
But you didn't need me to tell you all this...I'd be willing to predict anyone who responds to this thread who owns both the etys and grados will tell you the etys are better.
And if they say otherwise, I will edit their posts with my moderatorial powers
(j/k of course!)