I've had experience with three aftermarket hardtops. None of them fit or sealed like the factory top. The factory top if free from cracks is worth the money.
If you are talking about the half top doors with the sliding window glass, I actually like those - for the topless days, you still have the open feel of the lower half doors, and for the weather days you have a quiet glass window that opens far enough for tolls or fast food. As long as the doors match the top, it looks good.
1967 Kaiser Commando
2001 Grand Cherokee WJ
2003 Wrangler Rubicon TJ