The X411 should be covered with a good condom and have added lube (KY, J-Lube) for insertional comfort. A slight degree of inflation stiffens it enough for comfortable insertion. Totally, slack, forget about insertion! Once inflated, the upper portion will lock it well into place and flange avoids further inward migration (v. embarrassing when the inflation tube parts and you've lost the handle).
Be careful about foods that give you gas, you can suffer blowby! V. messy!
Inflation pressure is easy to control and is very comfortable for at least an hour.