I did. I find the HD598 boring and analytical. Way too much midrange, and not enough life overall. Sure, if you want a singer singing right into your ears its fine, but other than that, the Q701 does everything else better. It sounds more realistic and enjoyable. I find the tone of the Q701 to be pretty neutral to very slightly warm, and well balanced overall, with just a lack of sub bass, but mid bass in line with the rest of the sound. It also sounds more lively and fluid.
I don't think the HD598 compares to the Q701, though its a good alternative for gamers who don't wanna spend much on amping, as the HD598 is less demanding by quite a bit.
If anything, I felt the HD598 to be a poor man's K701 with even more mids.
I'm really not a fan of the Sennheiser sound for music.