Yes the RAF did use quite a few India 741's. In fact lots were supplied to the allies under the lend lease scheme but they were mainly issued to the lower echelon units as they were not well liked by our blokes.
I have most makes in my collection and I seem to like different aspects and features of all of them.
I love the antique look of the 16H and I would say that it a slightly faster bike than an M20. The Triumphs are light and lively with lovely gear box's. The Matchless's again are very lively with quite nice box's but some of the design features leave me speechless. The Velo's are just quirky and hand built and very sporty once you have them set up correctly. The Ariel is a very good all round bike with every thing more or less as you'd want it. Royal Enfield's seem very under rated. I really like riding my CO especially for convoy work, however the gearbox is not my favourite.
For sheer durability and reliability you'd have to go a long way to beat an M20, however they would be better if fitted with a Triumph gear box and clutch.
I also personally prefer a gear driven magneto as opposed to a flaying chain.
Finally I never go for a ride on my Indian......I always go for a wobble!! Ron