Very late response. But might help someone that wants to compare the two.
For metal of just about any genre, guitars are far more forward and pronounced on the 262 than they are on the UM3X, as are the singers. With the 262 I always felt riffs and solos were absolutely brilliant as were vocals, they were right in my face. With the UM3X I feel they are being pushed right back as though they are not important, I dont get the wow factor anymore which is a shame. The 262's shaped my musical tastes from a very mixed bag of stuff to almost exclusively metal and thrash metal.
For Rap or Electro stuff, the 262 has minimal bass, I stopped listening to rap altogether when I owned the 262 for that reason. However it did seem to cope well with electro house or similar genres of music as it copes so well with the mids. The bass in the 262 is punchy but theres not much of it which may bother some people, personally I found it quite shocking, its something I grew used to within a month or so and loved it after that. The UM3X has plenty of bass (its punchy and theres plenty of it!) and sometimes I find it overpowering when listening to metal covering the mids and highs which pisses me off no end at times. I find the UM3X great for rap.
RE262 does require an amp (was it 150ohm?). I ran the 262 with the E11 in the 18 months I owned them. UM3X seems to benefit from an amp but they definately dont require an amp to drive them to extremely loud levels.
As for detail. The UM3X is definately better in this respect, its got better clarity hands down and the instrument seperation is much better. HOWEVER, back onto the topic of bass, it interferes with the mids and highs when I really dont want it to and I find that ruins them.
I cant decide if I should sell the UM3X and re-purchase the 262's to solve the craving I have for in your face guitars.I think what I really want is a 262 with better clarity and detail. A straight forward upgrade.
