I didnt really like the show. At first I loved the fact that i could get to see the CCS characters again.... and the crossover with xxxHolic and the other CLAMP series...
but then the anime version only gets further from the original story in the manga, especially after the second season, and the ending was not even the same!! i hated that!
I really LOVED the OVAS though. (both Tokyo and Shunraiki)
I also strongly reccomend you all to read the manga. it's way better! in my opinion it's the best of all of CLAMP's work that said, im a huge fan of these series. but i think the anime is not good enough for it.