Hysol is the ONLY glue I use. It is thick and absolutely controllable. Even form-able to a point. It is VASTLY stronger than 30minute epoxy and never ever gets brittle which can be the death of a plane. I don't know about the West Systems glue as I haven't used it but Hysol has never let me down. Yes it's expensive. But lordy man ask yourself what you are using it on. A multi-thousand dollar plane deserves a glue that can stand up to the task.