Rift + touch for $400 is a super deal, I paid $900 Cdn for each of my Rift with NO touch controllers when they first came out.
I think 95% of the players who try the Rift will enjoy it and get great things from using it in flight sims. Is VR perfect - no. As stated, without being able to use your peripheral vision, looking directly aft can be a challenge - like Skuzzy said, a chair with castors which can pivot, or pivot on a fixed stand somehow, helps a lot in this area, I use a DX Racer with large 5" rolling casts and a pivoting base on it on a smooth surface for this very reason. TrackIR is still faster, and in terms of competitiveness, I would say hat+TrackIR is probably going to have a slight advantage, although VR players once they get accustomed to how it works in combination with the hat capability HTC has IMO can come very close, possibly even equal in terms of keeping track of a target.
4 hundred bucks. It's a steal really. Every person I know who tried VR in this game has been impressed, even with the few small disadvantages.