I've seen it twice now. My first time was in London in 2010 when I was briefly visiting the city with my mother. We sat in the Grand Circle and I honestly don't remember much about it, unfortunately. I'm not sure if I was too young to appreciate it for what it is (I doubt it, since I've always adored TLK), or perhaps the seats weren't too great, but my most vivid memory is of the people sitting next to us constantly having to get past to get out of the theatre for something
I would've loved for my first time to have been more memorable. Seeing TLK in the IMAX in 2003 was more memorable for me, lol.
I saw it for a second time when the tour came to Edinburgh in October of 2013 with both parents. It was the third year anniversary a few days ago, actually. This was a much, much better experience. We sat in the Stalls, about eight rows from the stage, which is honestly how you should see TLK should you be fortunate enough to get those seats. We were able to enjoy the Circle of Life scene, with the animals coming down the aisles, in all its glory. It was a wonderful performance and a great night. I was so surprised by how professional the tour version looked. I had seen plenty of shows in that particular theatre and didn't believe they'd be able to include some of the effects, like Pride Rock rising out of the stage floor. I was so shocked when literally every detail felt identical to how it did in the Lyceum.
I'd love to see it for a third time. I'm definitely going to make sure I see it the next time I go to London. In fact, it might be the reason why I even go back to London in the first place.