This wah sounds great and it's every bit as versatile as the Sweetwater description boasts.
I've found my happy place as far as the adjustment settings of the "Q" dial, frequency range sweep, and adjustable boost, and I don't stray to far from the settings that sound the best to me. Of course I do make slight adjustment changes when dealing with variables (e.g. room acoustics, changes in signal path and amp). The point is that the adjustments are useable, and with them you can create a wah pedal that is custom to your own personal preferences.
I really like this pedal and I'm happy to attest to its value, but what really inspired me to write this review is that I realized today that I've had this pedal for over three years now, and that's longer than I've ever had a wah pedal last. I play nearly every day, and although I take care of my pedals, this pedal is getting stepped on all the time and used aggressively, so that it's lasted over three years is a testimony to it's durability.
I have another 535Q on my Sweetwater wishlist just in case my current pedal dies, but like the Energizer Bunny, the one I have just keeps going and going.