I'm torn on Test Track.
On one hand, I see that it is a very popular attraction. As someone said, the thrill for those afraid of circles heights and actual thrills. It suceeds. It always has a line, and buisness wise, once it got open, it is a strong attraction for EPCOT, everyone can ride it, and it is enjoyable to 99% of the world.
But then there is the fan sense.
I mean the queue is great, it has a lot to see, which is nice (especially once EPCOT's management realized that keeping standby outside and letting FP run through the queue inside was stupid). You can always see something cool in the queue.
The ride itself is fun too. I mean going 60 mph in a convertable around nice banked turns when you don't have to do anything is fun. The scenes inside are interesting too. You don't just go for thrill, you see scenes first.
But on that same line, you really only care about the thrill on TT because there is nothing to learn in the scenes beforehand, so it takes forever to get to and then it is too short.
I think Test Track's biggest problem is it has no magic. There are few sounds you could hear outside EPCOT and think "TEST TRACK!". There is no good music. There are no scenes that you long to go back and see.
It's like LMAX. It can be a hassle to go see, and it's fun but not great.
I don't hate it, but I don't think I love it. I have not ridden it since last summer though I have been in EPCOT 3 times since then. When I go for long trips I make sure to FP it on my way to Mission:Space in the morning, but now once is enough.
It's there, I ride it, I don't long to ride it though and I don't miss it if I skip it.