I've used several slideshow extensions with lightbox features, but this one really goes the extra yard by providing a thumbnail scroller in the lightbox modal, and the fact that it intigrates with so many other ARI slideshow extensions as well as the most common slideshow extensions out there really makes it a valuable bang for your buck.
The module and plugin are really easy to implement.
I used with both ARI Image Slider and ARI Orbit Slider for showing (rather large) images within a clients portfolio.
I was really impressed with the nearly instant support (given the time difference) and the practical and concise solutions provided. I did require some help with an issue (Firefox) that he promptly provided a solution for in one bit of CSS for my template. I did have to do some CSS adjustments to get the INFO pane (image numbers and CLOSE button) to show over the frame.
Given my experience level (or lack thereof) with Joomla as a designer, I'd have to say the Pros definitely out weigh the Cons (if any). And the only reason for the Good vs. Excellent rating... there's alway room for improvement! And for the minimal price, it's like getting 3 for 1.
Simply said, a super extension and plugin!