At flows of this nature - imo the Gorge is the easier of the two runs.
They are both great runs and worth the drive but the #'s is just so much more continuous as many of the rapids kinda melt together at these levels. There is still breaks in between the rapids in the gorge.
As far as the fun factor - plenty of big waves in the Gorge but as not much great play as the numbers offers..
It is fair to say that right now the #'s is a world class play run. With literally so many surf and play spots that it is hard to get them all in. Add in piney in playboats at 3500cfs and again #'s get the nod as there is nothing even close to as challenging as piney down in the gorge.
So I would say that the #'s is the more challenging and if you like to surf big waves / holes the #'s has a much higher fun factor.. Yea skipping down a 6' tall - totally green wave at 1 & 1/2 last night did not suck
Dont get me wrong the gorge is still super fun and worth a evening paddle. But in a kayak the #'s is hard to beat right now.