You'll find that most people really lean one way or the other. The guys that like foam swear that paper/gauze filters like the K&N and Velocity suck. The Uni will definitely offer you better protection. I have a Velocity and run a pre-filter. I have yet to find any dust in the intake. I like K&N and Velocity because I HATE cleaning foam filters. I've had good experience with K&N too, so I went that route. If you ride in a lot of dust, then I would probably go with a foam filter like the Uni.
I have run both on different bikes over the years. I think the K&N type filters will flow somewhat more but I question if they are as good at filtration as the foam filters. I have no proof of that, and you can find opinions either way all over the net.
Both are good as long as you keep them clean and maintain them per the manufacturers recommendations.
If you use some type of pre-filtering method, the time between cleanings will be similiar. The K&N type filters are much easier to clean though.
It really comes down to personal preference. I run a UNI on my 700XX.
I gots to disagree with ya there tbird. I did the EHS big 3 recently. At first I ran stock filter with modded box and barker. Just got my UNI's in and adjusted the fuel map up a bit. Notice a significant diff under heavy accel. Not night and day by any means, but smoother and more "pep".