I am surprised by the amount of bad reviews here, which I can only assume are mostly from disgruntled old timers that oppose anything new. I really liked the expansion, not even only that, I think it was a lot better than the original Baldurs Gate in terms of story, presentation, dialogues.. and everything else really. I did not play Baldurs Gate 2 yet, so I can't judge how the story fits into the series, or if there are consistency issues or the like. But having played BG1 and then directly afterwards the expansion (which from the timeline of events definitely makes sense) I can say that it was very enjoyable. It did not feel at all like a fanfic mod as many others complained, in the contrary, the qualtity of the game seems a lot above the original BG1, which was just very barebones in terms of story and dialogues. Finally, in the expansion the companions come to life! The story is also very intriguing and how it was presented was amazing at times. The siege and many other moments were really really good. On the technical side, similarly to the base game I encountered no issues. So, having said that, if you plan to play through BG1+2 I definitely recommend to get this expansion. It is worth it!
I had the game on my to-play list since a long time, since it is a classic and I am a big fan of CRPGs. Now in anticipation of Baldurs Gate 3 I finally pulled the trigger and took the time to play through it. It was a great experience and it aged well enough to be enjoyable to play through. To my surprise it did not play quite as the CRPGs I already knew, having such little focus on story and dialogue, and especially because of the lifeless companions. But the combat, even though a bit clunky at times, was challenging and interesting. The setting of the game and the little story/dialogue bits were captivating and interesting and I am looking forward to continue with Baldurs Gate 2 soon, for which I have high expectations. On the technical side I had no issues and the game ran perfectly fine for me. To summarize I think the game is very good and can recommend anyone to play it and the great expansion Siege of Dragonspear.