Ask YC: Anyone using Google Site Search?

I'm researching different alternatives for implementing search in my site. For a while I have been thinking of implementing it using Zend_Search_Lucene. But one interesting alternative seems to be Google Site Search ( http://www.google.com/sitesearch ). It would cost $100 annually (for < 5k pages) and is a bit customizable. Time is a bit of an issue for me, so $100 is preferable to implementing search at this point, I would definitely spend more time on it at some point in the future though.

Has anyone tried it out or has anything to say about it? What do you use for search on your site?