I just replaced the top on my '99 Miata. After shopping and reading for a couple of months, I chose the Duetto Glasfold top. <http://www.duettomotors.com/miata/miata_tops/tops_glass_intro.htm>
One of the reasons I chose this top was because I liked the smooth design around the rear window. While installing, I was very impressed with the quality of design and construction.
The instructions they provide are very comprehensive and the special tools that I needed beyond the usual were:
1. A pair of long needle nose pliers
2. rivet gun
3. torque wrench that can at least register a range of 78-101 inch/pounds of force.
4. right angle ratcheted philips head screw driver.
5. double sided mounting tape.
6. patience :-) This was the first top I installed and over the course of a week, I probably spent about 12 hours to complete the install to my satisfaction.
Once the top was installed, it was very hard to close and I had to loosen the rain rail retainers to get it latched, even with the latches at full extension.
As you can see below, it was worth the effort.
After the top stretched out a little more, I took off the rain rail retainers, re-aligned the top and then tightened everything to spec. I am very satisfied with the top.
Daniel