I did a couple of searches for benchmarks comparing MySQL full text search and KinoSearch / Lucene.

While there wasn't much on Kinosearch (see KinoSearch vs Lucene indexer benchmarks), I did find this comparison between MySQL full text (plus some plugins) and Lucene - see High-Performance-FullText-Search.pdf, which indicates that Lucene is the clear winner in their comparisons.

Also see this PDF for a nice introdution to KinoSearch.

One of the things I like about the MySQL full text, is its integration into the main database, so that adding where clauses based on other columns is easy. But reading the benchmarks, this appears to have a significant deleterious effect on performance, so perhaps it isn't such a clever idea after all.

I see that KinoSearch 0.20 has range searches and filters - I'd be interested in knowing what effect these have on performance.

Clint