I own one of the vac-u-lock systems. It's clever and all that, but the leather harness takes time to slip into and is a fair bit of work to keep clean.
That and the dong-part sits a little high.
I have been looking at the feeldoe, especially since finding out about the realdoe, and consider it a definite option, for later.
That vixskin thing looks brilliant too, I might look into that...
But the harness part..
I think I'll use some rope actually.
I'm already into that sort of thing and the aesthetic of wearing "just" rope instead of rope here, leather there, etc, just seems... better... to me.
And there are a lot of pretty ways to tie a penis that are usable to improv a "harness" out of.