I purchased the toolset license about four years ago. Last year (or maybe the year before that?) I saw that they had upgraded some tools and I downloaded and installed them, but the registration key didn't work. I wrote them and asked about it and was told that my license, while good for as long as I had it, was only good for the version I originally purchased and if I wanted the updated stuff I had to purchase again.
That bummed me out a bit since that proviso was not listed on their site when I had purchased; they added that much later.
I will say that when I complained about that they did offer me a complimentary key for the later versions to placate me. I declined, though. I wasn't trying to wheedle a free ticket. Just thought that adding that after I purchased was a little unfair. Either way, with all the "tools" you get, I mostly just used the PDF creator.