Ok, finally got round to pick a pair of Grado's up (80e).
I am not a headphone expert so can't give umpteen comparisons and my other headphones are either modified by your good-self or so lefty that no-one else has probably heard them so comparisons there are pretty fruitless too.
I have listened to a few other phones whilst picking them up so this may be more helpful; AKG 550 (awfull, like listening through a tube with a very unbalanced sound ... sucked out middles and harsh treble) and AKG Y50 (almost as awful. Flabby bass but better mids/treble) and Grado SR325e (Good but I found some harshness in the low and high treble which the 80e does not have but the 325's have dfferent ear cushions so the difference may well be coming from there. Still obviously better than the other two). Granted, all not very scientific and done very quickly through a CA system. Even so, I thought the Grado SR80e suited my ears/listening habits best of the bunch, even if they'd all cost the same.
I know more about separates/speaker system than headphones so I would sum the Grado's up this way;
If you like the Naim* house sound ie. involving, rythm driven, not to hifi with great attack, smooth mids, an integrated bass and sweet but not super extende treble/soundstage ... you like these.
Also, Valve amplifier afficionados will probably like those; they (SR80e's) make those little micro dynamics which can make music alive stand out without sounding grainy or harsh, just very clear and focused.
If panoramic imaging, sub terranean bass and ultra extended treble are your thing, you should perhaps look elsewhere.
I find them subtle, attacking when the need arises and tonally relatively even. Equally important, bass is lovely textured but taught, punchy and snappy (I really dislike excessive and flabby bass).
I have never heard Grados before and there are a lot of conflicting opinions out there but have to say I am pleasantly surprised.
Fun then
* Whilst waiting for the phones to be picked they had a Naim Mu-so dem in store. I appreciate room acoustics where probably not ideal and it was playing from a Bluetooth stream but it sounded not great to me. The lack of separation was obvious as was the piercing highs and somewhat overwhelming upper bass. - Based on that I would not buy one for 'serious listening' purposes but it sounded somewhat fun and the small'ish size factor is clearly a selling point. - Still, having heard some of the good reviews I have to assume that the sound I heard is mostly down to bad shop acoustics.