I'm a player in the Shackled City adventures right now. (We've figured out the villain's plan and have just moved into the KR.) We're enjoying the adventures quite a bit, and our brand-spankin' new DM is doing a great job. The only negative experience for me has been the mental wrench of placing D&D -- which for me is default Western Europe -- into a jungle environment. And that's a problem with me, not with the adventures; I have the same cog-dis with Freeport, which I love.
Anyway, I recommend the series. So far the adventures seem to possess tight, well-constructed plots, but they're not so convoluted as to be nearly impossible to puzzle out. Lots of good "minor mysteries" to keep the players thinking, while the action moves on. (In fairness, I should reiterate that I'm not the DM, so it's possible that my DM adds, removes, or changes elements, and that might impact my recommendation.)