We spend the vast majority of our development time (bug fixes, performance improvements, and new feature construction) on Logos 5. As a result, L5 is our fastest, most stable, and most powerful study software ever. The performance improvement between L4 and L5 on Mac is quite stark.
If you're still using version 4 or earlier, you don't have to miss out! Today, I posted a quick explanation of how to get the newest/best version of Logos.
I'd encourage all of you to download the Logos 5 engine for free.