My car has an aftermarket sunroof, and it most certainly hasn't leaked. Perhaps in the future, but there's no trace of any problems at this point. It was on the car when I bought it w/24k miles (at 46k now), so I have no clue how much it cost. I can tell you that it's from a company called Webasto, and that the model name is Hollandia 300.
This appears to be the homepage for it. Mine has the same button as that second YouTube vid on the side there, for the 312 version.
I'd be willing to pay $500 for one of these, but no more then that. It's just a window in your roof that you can look through and/or open. It might be cool if there was stuff outside worth seeing, but I live in AZ... All that's out there is the sun, and I get plenty of that elsewhere.
I've never really taken pics of it specifically, but these show it in some form. Hope they help: