If it's not factory installed, the hardware and fitment is usually sub-par.
This goes for t-tops,sliding sunroofs,moonroofs and pop-ups.
The silicone weather strip needs constant attention, particularly later in life.Trim rings on the interior that screw into the bottom of the sun-roof line, bend and warp because of poor design. Then those flaws are hidden when the headliner gets it's final dressing.
The bigger the hole you cut, the more complicated it gets.
They can look cool, but usually end up being massive migraines....after market sunroofs are something I'd stay away from.