Grouping 39+

[Estu]

My shaman just hit 39 today. Until a few levels ago, he was almost exclusively a soloing character, but recently, I've decided that soloing is boring and started grouping. I've made my last few levels in Lower Guk, largely in the bedroom area, but the mobs are starting to turn light blue, and even/yellow cons are rare indeed. My experience grouping at lower levels has been that you generally try to camp even and higher con mobs, with some blues thrown in; is this still the case in high level EXP groups?

More importantly, what's the best place to group from 39 to 50 (or the best sequence of places)? I'm talking zones as well as specific camps. I know there are higher level camps in Lower Guk, but I also hear that Solusek B is popular. Suggestions?