My quick initial impression is that they’re the best Grado I’ve owned so far. Compared to my last owned pair, the GH4, they’re definitely a step up.
The RS1x has a more natural sound to them. The timbre on guitars and pianos is amazing. It’s a slightly darker sound, but not as dark as a PS500e from what I can remember. Instrument separation is still good, but it still doesn’t quite have a large/wide soundstage (does any Grado?).
If Grado could make the RS1X sound with a larger soundstage and great imaging, I feel like it would be perfect to me. I have a 3rd party g cushion on the way, so maybe that will help with the soundstage.
Aside from the sound, they also look and feel great. Also, the new Grado smell is slightly nostalgic for me.