Well since there are only THREE to choose from, it shouldn't be too difficult to get in touch with the companies and find out the info you are looking for. Chris from CTA Motorsports has been more than helpful to me in the past. As Hector said, it can be expensive to dyno after each mod that you do--it adds up to $80 to the cost of the mod.
AFAIK, people have the CTA or the KKM. Several people have said the CTA is better than the KKM. I don't know of anyone that has the OBX.
