Good video! You hit the nail on the head, one cannot really know unless one tries... last year I went on a "rotary bonanza" and purchased a shitload of different machines. Stylus, Thunder, Halo, Ego v.1, Kubin MC2, Kubin Max, Kubin Sidewinder, Inkjecta Flite 2.1, D20, and probably a couple more I'm forgetting at this time. In the end, I actually thought each had it's good and bad points (and by bad I honestly just think it was a total personal preference thing), but I came down to mostly using the Inkjectas for cartridges and the Kubins for traditional needle bars. I also STILL use lots of my coil machines (and purchase some, my most recent being one of Seth's v.2 Wiener Dogs) and think knowing what is out there and seeing what they are like is a huge benefit.
For example, the Thunder was one of the first rotaries I tried, and I have to say that it worked great, and I could definitely tattoo long periods of time without my wrists and hands getting tired. But there was something that just didn't click with me. In the end, it's not the arrow, but the Indian. Don't just scoff at something because you haven't tried it.
Meanwhile, I've actually loaned my Inkjectas to a few friends locally who wanted to check them out and they have been sold on them. No I'm not going to mail anyone any of my machines to loan haha.