I bought the Cayin N6 DAP a month or so ago and was using RHA MA750s in-ears with it. I already really, really liked the detailed sound of the N6, and was happy(ish) with the 750s but the combination was sometimes a little too bright for my tastes. Anyway, I just bought a pair of used Grado GR10s (not the Es) on EBay as the price seemed fair, and having never heard any Grados I was curious what the 'house sound' was like, and would be like in combo with the N6. Well, colour me hugely impressed. As they used to say on Friends 'Oh.My.God'. It's just so 'musical'. I knew/expected there'd be a leap in quality, but I wasn't expecting this much. Other folk here could perhaps describe things more technically, but in layman's terms the biggest difference to me is the way instruments just sound more 'musical': drums especially sound more like drums than sounds being made by someone hitting something! I know it's a cliche, but I really am hearing details on tracks I've listened to (literally) hundreds and hundreds of times before (eg The Cure 'Prayers for Rain'). Clear as a bell, no harsh treble, 'relaxing' in the best sense of the word, endless decay of notes fading into a black background, everything just seems to flow perfectly. Yes, there's the usual considerations about getting 'best fit', but seriously these things are absolutely beautiful to listen to.
I suppose I'd better look at selling the house and try for the GS1000e now I know what I've been missing (or at least perhaps the GR10es if there's much of a difference)...