As far as the operational safety, stability, reliability, maintainability, performance, and other aspects of bringing an LSA to market I have faith our FAA will make sure the Terrafugia meets all criteria for approval. It is a novel concept for a roadable airplane. MIT is one of the top aero-science research institutions- smart people, well-qualified. I have some thoughts about the Terrafugia though having gone through their website a little bit.

• The TF looks susceptible to wind drift operating in surface mode on windy streets or highways. The folded wings act like sailplanes extending the moment arm above the CG. What testing has been done for this? There would have to be a speed limitation if it can't be kept straight at highway speeds.
• A lot of electromechanical systems means a lot of opportunity for corrosion, misalignment of parts, wiring gaffs, early part failure and so on. In such as light vehicle this would have to be a pretty high risk to reliability. I do not think the type of people who will be flying them will be able to evaluate the risk to reliability in the field. This is exactly the kind of thing that you can't predict in a new design, the end-user operating environment. Perhaps a controlled experimental user group should be checked for a while to make sure the TF remains airworthy in the user environment since it has more complex systems than a typical LSA (or car).
• This TF isn't cheap at $200k and may balloon north of $300k by the time it reaches certification. You could buy two Skycatchers and have enough left for a couple of pickup trucks for that much. What is the predicted market segment for such a high priced, narrow mission-profile vehicle? Curious business model. You need to sell a certain number of units to ensure viability over time. LSAs were an attempt to reduce cost for low-end aviation buyers while this airplane drastically increases it. This may have ramifications to safety in the long run, particularly if not enough units are sold to fund a steady supply of parts, maintenance personnel and support structure.
• This vehicle obviously would do very poorly in NHTSA crash testing. The phrase "death trap" comes to mind. It has no real bumpers, airbags, anti-skid, interior padding, etc. It is made of aluminum (I think) which has poor energy absorption capability in a crash. Worse the proto has protrusions in the cockpit. At the very least it needs a lot of improvement to be considered safe as road vehicle. Even if the NHTSA grants a crashworthiness exemption for the TF, would you really want to be driving a car that can't pass an NHTSA crash test? Motorcycles have a high fatality rate and the TF will be on par with motorcycles as far as road safety.
• The Terrafugia website has almost humorous lack of specifications and data. They are withholding info until things pan out in the manufacturing, supply, design, and certification departments I guess, but the website is woefully inadequate. What are the details of the power transmission systems, flight control systems, folding mechanisms, ballistic parachute system, fuel system, where they are going to source the parts, how does it handles in air work, where is the Pilots Operating Handbook...? Who is going to perform maintenance on Terrafugias and where will the parts come from? I have difficulty taking it seriously until some of these things are answered.

It's a nice proof-of-concept vehicle at this point, a promising work in progress.