I would say 'doomed to a path with lots of challenges'. As there aren't all that many Sabres lying about, having one in your possession is a step closer to the ultimate goal and as mentioned in the video, having an early model could also be the starting point for a swap. Also, it's not impossible to get an early one running, but seeing as Kermit has two Sabres available, I can see Richard's point in selecting the later model.
Edit: I have uploaded a cutaway image here:
https://www.vc10.net/div/NapierSabre_cutaway.jpg It shows a bit of the complexity of the engine. It's an impressive beast.
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NapierSabre by Jelle Hieminga, on Flickr