This afternoon, I went to a super F3F spot that has been discovered 2 years ago and that we used during one day of contest of the french league. The only problem of this slope is that it is difficult to reach: 40 minutes of walk, and about 300 meters of altitude to climb, so you need to not take too much planes or equipement to stay light. I took only one Pike, my compact camera, the Go Pro, but also the 2 kg of ballast ...
The slope is very deep, and "capture" the wind very well. Because it is facing north, it is not too much influenced by thermals. Time to time you fly a bit faster, but the difference is not huge.
I was alone on the slope all the afternoon, so flew 2 hours non stop with 700g of ballast. The lift has been consistent during all the time, really a super spot !
Here is a short video I did.