Grado cables are great at eliminating microphonics, but horrendous with the twisting themselves into a knot on your upper chest area. I'm listening to my RS1e now, and with the right source it sounds amazing, but let's be real y'all: we all hate that twisty Y connector part of the cable. We despise it.
The SR80i was my first ever audiophile experience, and I loved it besides that evil twisty knotty Y connector from hell (that was part of why I sold it, and my friend who I sold it to has told me "yeah, that thing is way too twisty"). The fact that Grado says they've finally fixed that problem got me instantly hyped, and I ordered the SR80x immediately. I don't care about the headband, that's whatever, it looks fine. I do look forward to hearing how the sound has improved two versions past my old SR80i, and especially since these days I have waaaay more expensive stuff to plug it into! I hope it's as fun and versatile as the i version was.
Also, this is just stating the obvious, but X is the coolest letter you could possibly name a series, props to Grado for that.