In-ceiling and in-wall speakers are fairly limited in performance. This being said you can get good speakers for the money. Check out the NHT's. They are durrable and give you very good performance for an in-ceiling speaker. There are some very expensive in-ceiling and in-wall products that do sound quite nice for what they are, but they are not really worth the money. Surround sound is just not that demanding anyway.
Good luck.
Good luck.