Obsesseo is a run through of the I:33 Manuscript. It was made by David Rawlings of London Longsword Academy. The DVD starts with showing the main wards and follows with a demonstration of each technique in the I:33. Each technique is shown from different angles, fast, slow, and with verbal commentary. You can either watch it all in one go, or you can play a technique and be returned to the menu to choose another. This second option would be very handy if you're practicing with a small group. The techniques start simple with the opponent doing nothing, and progress with the opponent countering, then you are shown a counter to a counter, and then variations on the the theme before moving on.
This DVD would suit someone who wants to pick up I:33 quickly. It is simply a run through of the techniques. For someone familiar with sword & buckler it may offer validation of their own efforts, or it may challenge their thinking through an alternative interpretation. I found myself altering the techniques with some of the suggestions in Agilitas.tv's Sword and Shield DVD. It's a starting point, but not the final word in I:33 study. One notable contrast is that Dave recommends cutting from ward to ward, whereas Agilitas says that the I:33 explicitly states that you should not cut from ward to ward.
In summary, I am pleased that I bought the DVD. It has helped me to learn the techniques in the I:33. If I had to prioritise I would buy Sword and Shield before Obsesseo.
DVD Website: London Longsword Academy