ur only 125lbs? the ghost is gunna be quite stiff for u, also the fit between the two boots is completely different, the spk mold coming from the old salomon ellipse boot which is a 105 or 106 last i believe, and the ghost comes from the salomon falcon mold which is a 98 last, completely different widths and fits. That being said, the ghost is much stiffer than the spk pro, and ur spk kaos will fit exactly the same as the spk pro. And if u think the 25.5 is a tad to small, id sitll suggest getting the smaller size, the boot packs out, and u can also stretch/punch out the toe of the boot, getting boots too big causes nothing but problems. Regardless, u have to go try on the ghost, ive had spks before, and i tried on my friends ghosts because of how narrow my feet r and they fit super nice, but did not feel as narrow as other 98lasted boots ive had one ie: full tilts, nordica dobermans, nordica hot rod 125s, tecnica agent 120s, this mainly has to do with the liner of the boot, the ghost has a much cusher liner than most other 98 lasted boots, i own a pair of full tilts as well, and the fit on them is much more narrow than the ghost boot IMO, but go to a boot fitter listen to what he says, ive been fitting boots for 4 years now, and have done alot of custom fitting for customers.