But in my opinion it is not worth changing over until your sprocket wears out.
Before they came out with the slim carrier, I was concerned about messing up my chainline, so I bought another threaded sprocket. I planned to keep using the threaded ones. But now that the slim carier is available, the only reason I can think of to stay with threaded is no longer applicable. But, I won't switch until my spare threaded sprocket is worn out.
And I do not mind pulling the sprocket off to re-grease the threads every few years. I would probably do that even with the splined carrier, just in case I am in the middle of nowhere someday and need the hub serviced, I want to make sure that it is not frozen on.