I use it a bit, I think it is useful and the sub covers a couple of updates. That said Stockfish and LcO are, as you observed, free.
There are lots of strong free engines, but I do like Komodo. Hope this helps.

Hey, folks! I generally use Stockfish Dev versions for my deeper analysis using Fritz. When it comes to sites like Chess.com and ChessTempo, I use both the Stockfish and Komodo engines. 

I see Komodo Dragon 2.6 for sale, with a year's sub to updates, for $119.98. With so many different versions of stockfish, some updated nearly daily, what is the true worth of this product to someone? Is it basically just something for someone to gift themselves or someone else with or would having the top end Komodo truly help in analysis? 

Thanks!