Don't worry about either.

You're right, ejectors are nice when hunting birds with a shotty. Even the lure of low price would not induce me to try a double shotgun without ejectors. On a shotgun, they're just too functional to be without.

A double rifle chambered for a flanged cartridge is an entirely different matter. I've owned and used double rifles both with and without ejectors for years. The one I use the most has them, they're just an annoyance. They're just something else to go wrong, and make the gun harder to close, yet provide no offsetting useful service. Ignore the ejector issue and concentrate on the quality of the gun.

I prefer the .060" and .080" rims too, but the .035-.040" rims are fine. It just isn't an issue. The idea that a double rifle should be chosen based upon the avavilability of factory ammunition is silly. If you buy a new rifle, .470 is fine. If you want an second hand British rifle, avoid .470. You'll pay a stiff premium to get that caliber and it won't do anything better than any of the rest.
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