I've been running Avon Venom-R's on my F and have been real happy with them. But the rear tire has flattened out quite a bit down the center. I've got about 8500 miles on both tires, and the front looks like it is barely worn. I can't really tell how much tire I have left on the rear, so I'm getting a little nervous on how long I can go on it. I'll probably replace it pretty soon.
I would also be interested in now Metzlers work on the F.