It was amazing that stuff. I have never felt as good as that on any other opiate. There was one particular batch that one of the main good UK vendors had for a short time in the mid 2010s that was so good. They only sold it to their 'advanced customers', or some such bullshit, in the name of harm reduction. It lit up my pleasure centres like a christmas tree that stuff did. Sadly / fortunately it wasn't around for very long at all - just a few short months. Although I loved it and I felt great on it, I would have lost control for sure and ended up very addicted (and that would have been one of the better possible outcomes of me getting in too deep with something that).
During the time I was watching the RC scene, batches of O-DT only became available on rare occasions. I only saw it appear for sale on another 2 occasions but those later batches did not hit me in the same way. It was very much like post ban mephedrone as opposed to pre-ban. In my opinion. (Although O-dt wasn't actually banned at that time the analogy applies to the effects it had) Someone else said that another batch had been available before I first got into that scene, but I can't comment on what that batch might have been like because I didn't have any of it. If I remember correctly, I think the other person said that that batch was amazing too.