So I eventually did sell my RS1e, and I have some final thoughts on it.
I think the sound as an RS1, is still better than the RS1i. It can't reproduce the treble texture that the RS1i can, but it's a little better balanced overall. The soundstage is also a little wider, but the imaging isn't quite as good. It's very much one of those "This is more enjoyable to listen to, but not necessarily as technically good" situations. Bass on the RS1e is absolutely better than the RS1i to the best of my recollection.
That said, it IS a different direction for the RS1 and I'm not exactly sure where it fits in the lineup. I think in retrospect it should have offered more clarity; it takes a while to sink into the sound and pick out the parts you really want to listen to. This wasn't an issue in previous RS1 models. The RS1 excelled at texture and clarity as I remember it, and this RS1 doesn't really do either. It is now sort of an "ultimate SR60" and refines that sound to its zenith... the RS1 of olde was a departure from the SR sound, be it brighter and more treble focused (RS1i) or clear and balanced (RS1 of previous generations). I dunno. It sits at a funny spot and I'm sure one day we'll wake up and they'll have changed it again. I question whether Grado knows what to do with it; it's no longer the "high end" in their lineup (and hasn't been for ages) but it doesn't seem to offer anything truly unique to the equation.
As for pricing, I think its value rests comfortably somewhere between $400 and $500, depending on the materials used and personal taste.
So why exactly did I get rid of it? I did like it, but my office is jam packed with folks right now (we're working on several movies at once) and it just leaked way too much sound. I don't think it was necessarily intrusive to the people around me, but if I wanted to listen to the same song on repeat a few times I felt like I was pushing it on others. Plus I watch some pretty dumb movies and documentaries while I work. As I wear headphones 8 hours a day at the office, it seemed like a waste. I traded them for the Audio Technica W5000, a headphone that I remember getting a great fit on almost a decade ago, and searching through my old messages and comments reminded me very much of the RS1 of olde. And it still does: I don't have any fit issues so the bass is actually quite good... I don't actually think I could listen all day to a headphone with MORE bass than the W5000. Excellent female vocals too, something the RS1e didn't do as well as its predecessors.