Flexible, E-Z on the arm & shoulder, big sweet spot, you can dial-in power vs control with different strings. It's a little crisper than the Microgel version.
I am a 4.0 player with a full swing. I am very familiar with the past versions of the Head Radical OS. I found this one to be even better. The racquet feels crisp and provides plenty of power from the baseline and on serve.