After being a user of Accordance for a few years (BibleWorks before that on PC) I finally made the plunge and graduated last week to Logos 6 Diamond.
I was hesitant but it turned out to be an extraordinary piece of software and I love it.
Same for me. I would only add that the L6, in comparison to Accordance is the need for a more robust hardware in your machine. Logos is a power hog. Load time takes forever. Updating is a task. Buying Logos should be considered along the lines of memory, processor and hard drive. Example, if you have an old machine, this will provoke a problem. I am on a 2008 IMAC. The solution for me was adding additional memory, adding a prog called 'Memory Clean' and replacing my standard hard drive w/ an SSD. Load time was at least 10 min's initially, reduced to now about 1 minute. '
It's unfortunate that Logos does not tell you this up front.