[HariBhushan]

It's been around 150 hours or so on my Senn HD650's and i absolutely love the way they are sounding right now on my Woo Audio 3 + musiland monitor 02US combo.  I love it so much that i am willing to take them to the next level,
 
but I kinda do ned to replace my somewhat decent M-Audio AV30 speakers to something better like some Adam, Dynaudio, etc.. studio monitors.  So which should be the better step? $700 is the budget.
 
and if anyone has both, do the Senn's sound better than the monitors? thanks for your input.

 

[.Sup]

I would get better monitors. HD6xx are top in their sound signature, whatever else you will get won't be considered an upgrade but change of sound signature you said you enjoy.