my roomate got a pair for xmas. i'm no headphone expert, but to me they sound just as good as the mvr700s, but much lighter - and the mono switch almost 'simplifies' the sound a bit. i like 'em a lot. they definitely are pricey though. if you can find a good deal, go for it.
I got a set for christmas and i love them they are pricey but the 700's have been known to fall apart and ive traveled with these a bit and they are built real well i think they sound about the same as the 700's they are alot lighter and have a smaller ear area (dosent cover half your head) hope this helps
i think the mdrv700's are complete rubbish in the sound quality department. these sound a lot better. on par with the technics rpdj1210, but a lot more. if u can get a good deal, sure go for it, otherwise go for something else.
i think it would be hard to find someone that has had problems with the durability or reliability just because they are so new but from the using mine i dont think that is gonna b a problem if ur good to them they will return the favor