Welcome to the forum Erwan! Asking which is the better car won't be answered definitively. What I can say is that Hawk have also closed their order books with a 3 year waiting list with deposits paid. There is a list of people who want to order a kit from Hawk and your name can be added to that.

I can't answer the question about registration. I believe it's possible now in most European countries (you can ask owners of cars already registered how they managed it) but rules change from year to year and what is possible now may not be possible in 5 years.

The easiest route to ownership at the moment is to buy a fully built and registered car and export it to France for registration there. Either manufacturers car can be converted to left hand drive but the LB is definitely easier to do. I wouldn't recommend it on the Hawk.

The best place to find a car for sale is through full membership of this forum and club but suitable cars rarely come up for sale and get bought quickly.

Good luck with your search.

Guy