In addition, Yuri is always quick to answer questions and offer help.
The only "cons" this has is that the documentation is a bit difficult to read (very long, not extremely well organized and assumes you know Joomla pretty well before reading it), and that it doesn't use Ajax.
But I am guessing Yuri will implement an Ajax solution since he is constantly working and improving his extensions.
On a performance note, I haven't noticed any negative effect at all in comparison with others that I could tell were more of resource hogs. So this is very well coded.
Download this now, it's the Best!
I would love to try it out more than I have, but the fact that you have to enable Legacy is very disturbing.
Another issue I have with it is the lack of compatibility with other 3rd party apps, such as Gallery 2 and SMF or other forums.
Would love to have it if these issues could be fixed, hell, I'd even spring for the subscription (paid fee) as long as it was a one-time payment.
As is, I need to look elsewhere.
Nice job though! Wish I could use it. :)