I have both the PSI and Berea mandrels and bushings. The Berea bushings fit on the PSI mandrel somewhat loosely. Most of the PSI bushings can be barely fit on the Berea mandrel and some won't go on. Variances in allowed tolerances, I guess. So anyway, if Berea kits have to fit on larger mandrels, then the kits should easily fit on the PSI mandrels with the PSI bushings, too. Just buy the kits, you shouldn't have to buy the mandrel or bushings until you are working on a penkit that specifically needs them. The extra thickness of the Berea mandrel seems to make it a little sturdier. Something to remember if you have to replace a bent mandrel, like some of us have had to do. Hope this helps!