Over the Christmas break, I've been testing XTOL with FP4 and HP5 sheets and rolls. Using the Darkroom Automation enlarging meter to check the OD, it looks like XTOL in the 1:3 dilution gives true speeds with both of these films, at least with my cameras/shutters (brand new Copal and electronic shutter RZ).

I've also dialed in a HP5 800 push with this same dilution and the negs have a sparkle and crispness that is really lovely to my eye. Now to see how they print!