Pros: Detail, Comfort
Cons: Bass, Portability, Isolation
Audio Quality: My initial impressions were quite negative. It seemed to lack bass, and some vocals and electric guitars seemed very piercing with specific music. However after some (brain) burn-in, and some EQ adjustments I really started to enjoy my MS-1.
BASS: I can certainly say that bass-heads need to look elsewhere. The bass is definitely there, and with some equalizing, it can actually become detailed and realistic. However, there is very little "impact" and "oomph" with these... especially if you refuse to mess with equalizer. In comparison, PortaPros provide significantly more bass, but sound muddy/veiled and unrealistic in the process of doing so.
MIDS: Very forward. As I mentioned, some vocals and some guitars can come across as piercing at higher volumes. In my opinion there's a minor peak around 3KHz range, I tend to very slightly equalize those frequencies down. Having said that, the instrument separation and detail is excellent. If you're coming from cheaper headphones, you will probably hear details in the music that you had not noticed before. And even though I complained about "SOME" guitars and vocals, most of the time MS-1 sound terrific. Acoustic music sounds especially realistic with these headphones. In fact if it wasn't for non-existing sound-stage, you would feel like you're at a concert.
HIGHS: Again, very detailed, I recall hearing a track that had some high frequency 17-18KHz sounds that I have never noticed on the PortaPros.
Music Overall: MS1 perform fantastically with Acoustic Guitar. They are also great for Most modern Rock, Pop, Indie, and Metal. I think the obvious weaknesses would be Hip-Hop, techno/dance or any bass-heavy music. Keep in mind that bass on these is still much better than ibuds and probably any $10-30 phones you can find. I believe that once you get used to the sound signature of these headphones, you will never be able to go back to anything lesser, because the music will not feel as exciting and life-like through other phones.
Isolation: is non-existent. You will hear everything around you. And everybody around you will hear your music. Do not try to use these in close proximity to others, or in noisy environments. And with the long thick cord, these are not exactly portable.
Design: Yes they look cheap and rough, and they also look like they were made in the 80s. I actually like that... but I don't think that these would be currently considered "stylish". Of course if you're buying headphones for style, these are unlikely to be on your radar. The overall design is very functional. I think the most glaring issue with Grado design, is that the earpieces rotate 360 degrees. This rotation twists the cord around, which is not good, so watch out for that.
Durability: I had these for 7 months now. No issues so far. I don't baby these, but I also don't abuse them. I think these will last many many years with normal use. There's not a lot of parts that could break. No colored shiny surfaces to scratch. In fact, my MS1 look almost as good as they did brand new... but then again, they looked pretty rough to start with.
Comfort: These are on-ear phones, so if you are used to around-ear design or earbuds, you will probably not like these at first. The clamping force was also a bit too much at first and made my ears hurt. I bent the headband a bit, and now I can wear these for 4-6 hours without any comfort issues.The new earpads were itchy. Some recommend washing them... I just replaced them with some older well-worn earpads that I had lying around. Currently I have no issues with comfort, and I can wear them as long as I want to. MS1 are also very light so I don't think the weight is an issue with these.
Value: These directly compete with Grado SR60/SR80, Audio-Technica ATH-M50 and Superluxes among others. And as much as I hate to say it, the other headphones may provide slightly better value for the money... not by much, but still. It will depend on personal preference more than anything else. I can't speak to how much better or worse SR60 is, but by all accounts, the sound is very similar, so you may indeed find that SR60 have better value ratio. If you can find M50s for under $120.. those may provide better SQ as well as isolation.
I bought these partly because I wanted something different from the mainstream, and also because of all the rave reviews these receive. Overall I'm satisfied with these, and I think they were worth the money I paid for them, but I'm already thinking about upgrading to more expensive phones. I'm looking for something that has accurate and realistic bass response,soundstage, and slightly less forward mids.