There is no doubt that the stock Model F XT has the best feel, undoubtedly since it was manufactured when IBM was charging $350 1984 dollars for it, about what a dot-matrix printer cost, and about as complicated.
I can't abide the layout of an F XT, or even an F AT, for that matter, because I use both number and arrow keys all the time, and switching between them with NumLock is a nightmare.
However, for me, a modded F-122 terminal board gives me everything I want, plus a bonus set of function keys and a dozen more spares at the top.
When you take it apart to move barrels and springs around to achieve a very-near-ANSI layout, you might as well do a bolt mod. It is much easier than a Model M bolt mod, and you can use normal nuts and bolts from the corner hardware store.
While you are at it, do a floss mod, too, and you will have a exquisitely delicate behemoth that is acceptable in polite company.
Unfortunately, the F-122s have now become as expensive as the others, and harder to find.
