We used V.9 for three years. It was quite satisfactory, but not nearly as good as 10. My estimate is that 9 was about 95%-98% accurate, 10 is much better than 99% even after 3 months vs. 3 years of training. That might not sound like a big difference, but it makes a huge difference in time spent proofreading. Doing a letter in V9 which had to be perfect was a painful experience. No problem at all in 10.
