You'll likely want comments from those who have owned both...I haven't. FWIW, I enjoy a little extra colored bass as long as it's tight and textured and not bloomy and loose. The mkII hits hard and with authority. There is nothing loose or bloomy about it. I listened to the new Daft Punk a few days ago and was blown away at how well the MkII handled the bass. Jazz, Blues and Pop with a good bass line play out very well also with the MkII.
I don't feel that I'm missing anything at all when it comes to the bass/sub region. While I'm not a bass head, you can call bass head light. And I'm very pleased with the full spectrum on the MkII.
+1 well said