I don't know about the car itself but NRE gets a bad rep as being over-priced on his engine packages. Anyone who has built a high end engine regardless of the make should know that top shelf engines from respected engine builders don't come cheap. Heck, even in the Buick community there are plenty of examples - RPE, DLS, Zimmerman, Duttweiler build top shelf engines and none of them are cheap - I'm sure there are good shops that can build the same thing on paper but will it hold up? You know the saying you get what you pay for.
As an example, I am in the process of building a twin turbo 455 LSx for my 1970 GS. I have spoken to several high profile LS engine builders around the country - Dan at DLS, Kurt Urban, LME, Virginia Speed, and even Tom Nelson himself. He was actually a very down to earth and knowledgable guy who was more than willing to share information concerning my project. I guarantee you they would all come in within a couple of thousand dollars of each other if quoting the same engine. The difference is that NRE is offering COMPLETE packages including headers, turbos, wastegates, engine management, fuel pumps, dynoed, tuned, etc. If you take the time to think about it and do the math, when you take the "cheaper" price from another shop and then have to come up with all the peripherals on your own and figure out how to package it, tune it, etc. you will have the same amount if not more than what he is offering.