Are they soft shooters?
How reliable are they? Prone to any problems?
How available are parts?
The Remington Model 11 is essentially the same as the Browning A-5 shotgun (with a few minor differences). So without getting into disagreeing or agreeing with other posts, my 30 years of experience with A5s says this:
No, they are not soft shooters, neither are they particularly hard kickers. The recoil operated system does slow down recoil so it seems like it takes an eternity for the gun to quit recoiling, but since the impulse is spread over about 1/8 of a second it really does not hurt even in a T shirt.
While they do not cycle as fast as some of the newer shotguns, they do cycle much faster than most shooters. I have fired my A5 as fast as I can pull the trigger, and it takes about 1 second to completely empty all 5 rounds. If you can shoot faster, maybe you will reach a point where that is too slow, I don't know.
The Auto-5/A-5/Browning's Patent Automatic 5-shot Shotgun design is absolutely dead reliable under any conditions when properly maintained. Once you figure out the "mystery of the rings" you will have a shotgun that will positively cycle everything from popgun trap loads to heavy 2-3/4" magnum field loads. Once properly adjusted, they will cycle no matter what as long as the shell goes bang. That said, it all depends on the quality of maintenance this particular gun has had over its lifetime.
Having said that, I will say this: Remington Model 11s have not been made for 60+ years, so parts are hard to find. If you discover a problem after you buy it, you will have a $200 closet ornament. Unless you have a reason for specifically wanting a Rem Model 11, I would pass on the gun. If you want a gun of that design, A-5s are available for just a little bit more money, and parts are much more available since they were manufactured until 1999 (do not buy an A5 made between 1940 and 1953, they are just rebranded Rem Model 11s).
If you are just looking for a shotgun to get your wife into shooting, buy a Remington Model 1100. Gas-operated means soft recoil, and fewer parts means easier to maintain and service, and all parts are available.