I used to buy this when it was coming out (Back then, comics were cheaper. Boy, I miss those days.), and I thought that the first year or so (Heroes Return.) with John Romita Jr was really good. That Destroyer arc was the best, as I really did not know about the character before then, and that made me really dig him. After that, there was some good stuff, but it started to lose steam. I think that Jurgens should have left a lot earlier (Say, after the death of Odin.). Overall, I think that Jurgens was underlooked, and I would classify the Dark Gods storyline as a classic. If just for the first year, I would give him either a B or a B +, overall I would give him a C or a C-.
I left comics before Jurgens run and didn't return for ten years which it seems is true for a lot of people. The first thing I read was his entire run with the Oeming finish. The first fifty issues were a delight and the King Thor Reigning took a shift in mental gear to appreciate and had some definite flaws but was a worthy exploration in a different take on Thor. Jurgens tarried longer than he probably should have but I think had he been allowed time to finish in the manner he wanted that story line would be more appreciated. I truly enjoyed all of volume 2. I liked a lot of the Busiek/Perez Thor in Avengers vol 3 as well.