First off, I am not a tire tester. I just ride bikes.
Most of my riding is done on my Kona Jake the Snake cyclocross bike and most of that riding is done on rail trails. This is what forms my "test bed" for trying out various bike kit.
The rail trail I ride on is comprised of gravel, stone, lime dust chip, and slimy clay. During the fall season, a layer of wet decomposing leaves covers the trail and can make traction interesting as any minor inconsistencies in the trail are covered up and when wet they can be slippery. There are no hills to speak of - just gradual inclines which often take several km to cross. The trail is ideally suited for knobby cyclocross tires although regular hybrid tires (700x30-38c tire size) suitable for commuting also work well.
During the summer months, I was using a set of inexpensive commuter tires which quickly disintegrated on the gravel. They offered OK low rolling resistance, but were a little sketchy when the ground was wet. Due to a dumb move on my part involving a drill and my bike rack (don't ask...) I had to replace the rear tire. I opted to put the original tires the bike came with back on the bike until I got around to getting some better rubber. Once they wore down, I opted for the Schwalbes.
These tires are about mid range on the Schwalbe line up and list for 33 dollars cdn each. Front and rear tires are the same but need to be mounted so they rotate in opposite directions for best traction. This is similar to some old Continental tires I had on my mountain bike and is no big deal, but care needs to be taken when mounting them lest they end up on backwards.
For the use I am putting the tires to and my physical size, the 700x30c size and relatively high pressure the tires max out at (55-95 psi) is about perfect. I usually run them at max psi since the trail I ride is fairly hard packed so skidding out on soft dirt due to extra hard tires is not an issue. This results in a much easier effort in maintaining a higher rate of speed on the trail - in fact, I find that I have gained a couple kmph in average speed since swapping to these tires versus the old ones which were bigger (700x35c) and lower pressure (80psi max). No surprise there, but it is good to get the bike feeling more like a road bike that can take a hit and less like a road bike pretending to be a mountain bike. :)
They handle gravel very well and are not squirrely on larger stones. Patches of wet clay are not an issue and the bike does not become unsettled when they get hit at speed. The treads do not pack up, and shed dirt quite easily.
On pavement, the tires handle well and do not buzz excessively. In fact, they are not much louder than a set of normal commuter tires. Cornering hard on pavement will produce a bit of shaky handling which is to be expected from a knobby tire. And like all knobby tires, wet pavement is not their strength.
Would I recommend them? Yes. I have no idea if they would be suitable for competition use (likely, the better ones which are much lighter would be good) but for what I am doing, they are about perfect.