I'll chime in here on the tire question. I still have the stockers on mine.
I went over to HighFive's house this past weekend and while we were running around his track, he left me pretty easily and it didn't make sense since I KNOW he isn't faster than me, lol. Well, we swapped bikes after a couple laps and I found out why he was so much faster. The D606's make THAT much of a difference over the stockers. It was night and day different. I was sliding all over the place with the stock tires and the 606's just STUCK.