I beta-tested MS Windows 7, 8 and 10 - and have been invited to continue with the program as 10 evolves. I have also beta tested MS Office for as many years. Similarly, as a photography student, I once trialled a pre-release version of Adobe Creative Suite - though not the entire suite.
I have had an interest in computers since the early days, way back when they were loaded from cassette tapes and operated via TV screens and you had to write the code yourself. Yes - and I later had an Amstrad PCW9512.
Things moved on and I just became an end user of proprietary software, like the majority of users now. I still like dabbling a bit with alternative systems; before this current installation of Mint 17.2, the last Linux I ran was SimplyMEPIS 8.5. However, both have been alongside mainstream contemporary Windows.