Pros: Soundstage, details, quite neutral sound but not totally analytic, you don't want to take them of.
Cons: Not produced anymore, some elements need to be replaced due to aging.
Those are AKG K-240 Sextett cardan from mid prod. I bought them on ebay for ridiculous price. If you want to go for Sextetts, keep in mind that elastic bands, inner sponge and ear pads are likely to be replaced. K-240's (MKII) are in production so it shouldn't be a problem though.
As for me, pads are a bit too flat, which combined with a bit bulky plastic grilles makes them little uncomfortable. I used thicker ear pads and now it's all fine. Original cord is good enough, head band seems to be indestructible. Materials and construction are great. Environmental insulation is rather low (semi-open design) so if you want all the details, listen to the music in silence.
How they sound? Well, those are the best sounding phones I ever listened (compared for example to Senn's 5**, AKG K-530, Koss Porta Pro and few cheaper ones). Soundstage is wide and clear. No lacking in bass and heights, mids are excellent. Nothing really dominates, response is quite flat. Those are fairly analytical phones, but not totally dry. Few minutes ago I've listened to Vivaldi (Four Seasons). To my surprise, for the first time I heard someone cough... Three times. Yes, you will hear all inperfections of the recordings. I'm just so in love with them.