If you don't mind a third party opinion - I've heard these three in rapid succession, and while the wa22 is definitely more dynamic and resolving than the woo otl's, it still isn't as fast and detailed sounding as a Zana. It is about what you would expect from a premium transformer coupled woo amp. I'd hesitate to say that it is closer to a zana than the w2 in signature, but it is definitely somewhere in the middle. Note that as a balanced (push pull) amp, the wa22 has higher power but also double the output impedance of a single ended design, so bass is actually going to be slower with more bloom when you run it that way. Noise and distortion (excluding common mode) will also be higher.
I personally prefer the mainline over all three of these as an ideal match for hd800s (to my ears), but they are certainly all fine amps - so identifying and satisfying your preferences becomes the trick.