I have a Nickel barrel on the CVA Staghorn and blue barrels on most of the other rifles. Which is easier to clean is really a mute point. They all have to be cleaned. Whether stainless will clean faster is hard to say. It will be easier to spot the crud on the nickel and stainless.

The stainless might be a little more forgiving to those that do not clean right after they are done shooting the rifle. In the rust department the stainless will give you more time before it starts to show rust, but they all will show rust.

I personally do appreciate the nickel barrel when I clean the rifles. I can spot the fowling much easier on the nickel. I am sure stainless would be the best of all three and most expensive.