It is quite amazing how many different style replicas there are. Some are much closer to the 'right' lines than others, and there are even some B-model examples out there.
The Stewart and Thunder Mustangs are my favorite. Most run on Chevy V-8's, while a few replicas actually are powerd by Allison V-12s and a mixture of other inline engines that can fit. The best thing about them is that they fly more well behaved than an actual Mustang.