The D1 has been my favorite mold since its inception and the 400/400s plastic has been the plastic that suits my game the best. I throw sidearm using a pinch grip instead of putting a finger or two inside the rim. The 400 plastic is the only plastic grippy enough for me to have a consistent release point. They are supposed to be overstable but in reality, the stability varies greatly from disc to disc. I actually love this though! I bought 3 of them this time because they are hard to find anymore. Two were very stable, and one was bordering on understable. The less stable one has become the heart of my game play now because in various winds, I can still use it with just a slight change to my line of aim and/or giving a bit of anhyzer. I gave one of the stable ones to my son and it works well for him. I'm saving the last one to replace my current overstable D1 for my long right dogleg shots. The new one fades out hard so it will be perfect for those shots. Overall, I hope as the COVID restrictions ease, that Prodigy can ramp their production back up so that the 400/400s D1's become widely available again. Other than my putter, they are the most useful discs in my bag!