I ride my 990 year around here in Vancouver and have Conti Trail Attacks on a 19/17 set up.
These tires are excellent in the dry and confidence inspiring in the wet. Good on graded dirt and gravel roads and passable on semi slick conditions. Anything really wet or muddy then you will struggle.
I rate them a great all around tire and the gain on the standard Scorpions for those riding 80/20 hiway/dirt roads is easily noticed.