So, the top my my Miata is only 3 or 4 years old, and the vinyl is still in good shape, but I got a little crack in the plastic window. In this ridiculous southern heat, the crack ended up being a cancer and the whole window came unglued pretty quickly. There isn't any really good way to fix this that isn't just a temporary bandaid, so I decided after almost 20 years of convertible life I'm just going to put a permanent hardtop on it.
With Mazda hardtops being at ridiculous prices both new and used, I went with an aftermarket fiberglass top. This makes it cheaper, but also requires a lot more prep work and I've already spent a lot of time drilling holes, sanding, etc, and over the weekend I sprayed the underside with primer in preparation for paint. Really hoping I didn't make an expensive mistake getting an aftermarket one, but won't really know until it's fully assembled and on the car.
I've seen people online that have both liked and hated it, but most of the people who didn't like it just put it together and bolted it to the car, and any fiberglass part really needs work done to it be good. People also say that all Miatas leak and they just don't know how to properly adjust a top.