Perhaps others that have seen it in various places can comment, as I've only seen it once (Toronto in May 2011). But I really feel that the quality/ability of Young Simba makes or breaks the show.
'Just Can't Wait to be King' is my favorite song, and the actor just couldn't pull it off. I think he was just a bit too young. His overly prepubescent voice bothered me for most of the first act, and soured my mood the whole time.
I think I remember Pete saying (not sure if it was on the boards or the podcast) that he wasn't impressed with the last time he saw it either. (Though I'm pretty sure he enjoyed it originally).
Still an AMAZING show as far as everything else goes (other actors/set/costumes/music), but when such a lead role isn't up to snuff, it will drag down any musical. Hopefully the traveling company coming to Orlando is outstanding!