I'm not running a Kalamar campaign, but my last campaign (homebrew) was heavily influenced by it. I like the setting in many ways, but not in a few others. For example, I would have preferred it if they had offered some different races besides the core ones. Granted the DM can always change that.
The books are all of excellent quality, and the Atlas is one of the coolest RPG books ever made. There are around 10 published adventures, which have excellent maps, handouts and random encounter tables. Really, the production values on the whole line are superb. I wish all companies took as much care.
There are no epic level NPCs running around. The setting can easily support low magic or no magic house rules. Want illiterate frontier dwelling barbarians? There's an area of the game world for them. Want a jungle setting? A desert? Pirates? City based adventuring in the heart of an empire? Dwarven kingdoms? Elves (god help you)? You can find sections of the Kalamar game world that support any of these. They are internally consistent and really fleshed out.
Some people say Kalamar is boring, but that's a function of their own (lack of) imagination, I think. The setting is an excellent base upon which to build. It can morph into whatever you want. Hmm. Unless what you want is Forgotten Realms. But in that case, why not just play FR?
Wicht had a story hour about a year ago that was set in Kalamar. You might search for it. Also, Arcady, a poster who comes and goes, runs a campaign in Kalamar. I don't know if he has a story hour, but you could search for his comments about the setting. He's a vocal and articulate supporter.