They are actually pretty amazing sounding ,very well balanced w/ a bass response better than a few higher priced "full sized" HPs. They may be better performers than just about anything below the "Tesla" series in the Beyerdynamics offerings. If you're comfortable using "on-ear" HPs these may be better than anything else that is available !
Check out Tyll's review of them on Headroom, his description of them is pretty "dead on" as far as I'm concerned ! I preferred the t70p, but the DT1350s may be the best of their class.