I got my hands on my first 150 SV last year, it was a car that the first owner had finished building in 2009 had had a few outings in it then his health had started to fail. So when I bought it with less than a 1000 miles on the clock there were issues. Particularly the bogging down at low speed, she just was as lumpy as hell. I took it to Luke Stevens at team Leo's Motor sport where he discovered that the throttle position sensor was wired round the wrong way ! After that was sorted it did run a lot better , but still not how I would of expected, so he took it down to the Two Steves where they transformed the car with a remap, she now runs as sweet as a nut and an absolute pleasure to drive. As I understand it took Caterham three remaps to get the 150 sorted, by the time the third one was done Caterham had already made the decision to drop it, they could buy the 140 from Ford straight out of the box and drop it into the car without doing a thing. Prices were kept the same,so as DRH comments , without the cost of throttle bodies Caterham were cutting their costs. I have the 5 speed gearbox which I find really good for touring , as DRH says you will have to think of what sort of driving you are likely to be doing as to which box you may find best. Good luck with your testing. Kingsley.