I tried Neutron and while it is pretty and such I find PlayerPro to still reign supreme. PlayerPros EQ/DSP is above all as well as it's lockscreen features.
I liked the always visible spectrum analyzer in Neutron and I hope they can overtake PlayerPro with futher development.
I did not like the side-of-the-screen arrows in Neutron, but that may be due to the Atrix resolution. At a higher DPI they might work better.
BTW: I am a trained audio engineer and I make a living in sound.