A loaded question...Klein and CW ??? I have campaigned two Electric CW Sprints for over 3 years now. If I was to start racing Nitro Sprints I would go with Klein. This is what I have observed first hand that makes Klein a better choice over CW. IMO:
Dennis supports his team and his cars like a mother hen. Parts are readily available, at your LHS or online. He and his team drivers are truly into helping you out trackside. BTW, the R&D Driver races in your area. The cars appear to be easily to set-up and race on any surface. Cars are made of better materials.
However, there are several other options!