Detail on the k550 is very good. they are very sensitive. But 701 has diffrent treble. If you dont mix up upper treble with detail, they are both very detailed. But they sound diffrent. Why would you switch, when you are happy with the 701. Some people think 701's soundstage is "unnaturaly" big, so for them, better would be smaller? In my oppinion you have to compare side by side and make your own desission. At the end its tast.
I heard that the K550 is bassier than the Q/K-701.