I love Ikelite. This is my second Ike housing, the first for the D100.
I just got back from the Galapagos on the Aggressor. At Darwin, dove with the 10.5mm to take pixs of the whale sharks. The 8" dome port is a great dome port, but with the 10.5mm, there is no true lock to make sure the port is attached to the housing. For all other lenses, the port is locked, for the 10.5mm, you push the port on, and rotate to the stop to keep the port on. At depth, there is absolutely no problem. The port is staying on ( i think probably due to the high water pressure). The problem is when you get to the surface.
Getting on to the panga, i handed up my camera, got myself into the panga, looked over to attend to my camera and the port was partially off. About 10 cc of salt water in the housing. F**k!!!!!! I think what happened was when my buddy helped to grab my camera out of the water, the port got twisted and part of the port got pulled off. Luckily the camera and lens were fine.
I dove the rest of the wk with the dome port and there were no problems. Of course, i retired the 10.5 after the scare. I made sure to use lenses and port combos that were locked in.
So warning to everybody, be careful using the 10.5mm with the Ikelite 8" dome port, especially in surge and strong current. I wish I hadn't sold my 6" dome for the 10.5mm. .....