I have read a review that says the 23 disc set is complete.  You can also
see the distributor notes at www.hbdirect.com

I don't know of better reviews ot an entire set of the Haydn's than this
set has received.  If you look at the individual CD's, many have won a lot
of recognition.

They are also available individually, and in 3-disc and 4-disc sets if
you only want certain ones.

Ray Bayles