My second shot at TSHOOT exam was much better. I went to another testing center and did not experience a single glitch. Out of 35-40 questions I got only one wrong.
I used Boson's practice exam during the preparation to one of the previous Cisco exams before and was really disappointed. The practice exam was not hard enough and there were few errors, but I was very pleased with their TSHOOT simulator. It is probably even more difficult than real Cisco exam, but no simulator can replace on-the-job experience.