Never tried the free version but I share MMLs sentiments. JMB make good, solid software. AutoGallery SQL is excellent. The only flaw I would say is how it handles archives. Another one to consider is
comus thumbs . This also has a free version (but with a skim). The paid version is $295.
I use both scripts and I'd say for anyone budget conscious, jmb is the best money spent (as long as your sites don't run massive archives...then again, maybe someone else has managed to find a way to manage them).