I was torn between the Mordax 90 and the Mordax 105 and ultimately chose the Mordax 90 because it was close to the maximum size of most of my toys that I can insert completely. It was the correct choice. It was a moderate challenge to insert it fully the first time as each ripple passed the my sphincter muscle ring and into my rectum. But after a couple of minutes of slowly insertion I found myself sitting balls deep on the Mordax 90 with the tip pressing through the recto-sigmoid junction. It's a delicate balance of softness for the length and diameter with it being a little softer than I expected. This makes it a little more flexible and bendable as it's inserted. So, changing angle or using a little guidance with the hand is necessary to slide it in. The softness helps it be a bit more compressible to allow it to squeeze through those tighter places in the rectum. The best part of the compressible nature is how changing the angle while compressed allows it to pop in short distances as the compression is relieved. The ridges are noticeable as they slide in. But it's when the Mordax is on its outward stroke when those ridges are most wonderful. I look forward to riding this through many hours of orgasmic pleasure. ⭐️⭐️⭐️⭐️⭐️ - G.S.