well.
I, too noticed the gaps, and frowned on it; definately need to fix that. These games have been overdone, and I do believe you know that, but yours at least as complete 360degree turning ability, which added (just a little bit) of depth into this.
I didn't like how long the exhaust took to disappear, and this point probably angered me the most because I didn't really see a point to having it linger there for such a long time. I don't know if this is what you were going for or not, but (in my eyes) it was a little more than what was needed.
I was frustrated when I got into (about) my second minute. I had just been so frustrated at the tail (which was too long to begin with at all) and at the places the boxes has decided to pop up (next to the tail much, plz?) .
Regardless, good job.