OK, I'm not afraid to give you my silly opinion. I have researched and observed most of the cobra's out there including the Superformance and the ERA.
Opinion: ERA for authentisity, appearance, engine placement and attention to detail.
Superformance for fine production car quality, great paint and std. features, although not authentic body shape and engine placement, good for those that want a big company product.
Both cars are very good, but I appreciate the ERA most.
Bill