Clicks on just as easy as any other lens without the goggles.
Regarding the OP's question: I'd take an M3 over a Nikon F anytime. Just posted the Nikon F as my most disappointing camera ever in another thread in this forum: it has nothing over the Nikkormat FTn. My Nikkormat FTn's are black with the early styled full metal lever (identical to the Nikon F), they have a meter in a much smaller finder, and a meter read-out on the top which makes them ideal companions for other camera's that have no meter. It's real easy to use them as a spotmeter wthout having to lift them to the eye.
The M3 is the summit of mechanical craftmanship. Maybe an Alpa or a Robot Royal 36 could compete, but I really cannot think of any other camera
The Nikon F is really big and heavy. If I were travelling/sightseeing, it would be way too much to carry around.
Unless I needed a long telephoto for wildlife or something, hands-down it would be the Leica.
And frankly, the F is kinda clunky. An F3 or an FE2 is much more my style.
I'll take an FM over either except that I have become aperture preferredizied. So give me a Nikon FE and call it a day.
I see that many of you are owned by their own camera.
I have an M3, two M4's, and an M6. I can't say that they are superior to a Nikon F in any way other than that their winding action is a little smoother, and that they may focus better in low light. But the M cameras are not as reliable, cannot focus closely, and don't allow you to see exactly what the lens sees.
As far as weight is concerned, an F with an eye-level meter weighs roughly the same as a Leica M. I like to shoot with a 28/2.8 AIS lens, which weighs about the same as a 35mm Summicron, but less than a 50mm Summilux.
If your goal is to simply take good pictures, then the F is the obvious choice. You can spend the hundreds of dollars you save on good lenses or film.
Well, whilst I agree that the Nikon (or Nikkormat in my case) and the Leica (M6 in my case) are almost equally heavy as camera bodies, the minute you start adding extra lenses to the mix the weight and bulk factor starts to favour the Leica. Unless the trip is oriented towards car travel and there's not too much walking around then the weight of the Nikon kit can see you getting more and more reluctant to haul it around.
Frankly, my own travel kit now is basically the much lighter Bessa R4A for B&W and the Fuji X10 for colourful 'snaps'.