BV I totally agree with your sentiments. Given that it is near impossible to recreate all the hardware of the period accurately it is indeed a great film for the reasons you mention.
I would also add that it is a great reviver of memories for those of us now heading into our dotage and that is no bad thing. Helps to keep some distance between us and the funny farm.
Incidentally as the reflector gun sight of that time did not predict the lead required for deflection shots a great deal of practise by both pilots and air gunners was undertaken with clay pigeons and shot guns. A great deal more fun than squatting in a simulator I think.