I went with 9x26-12 Evo's on all four corners mounted on STI HD Beadlock wheels. Evo's do run slightly small so 27's shouldn't pose a problem rubbing, however the P-5 is a narrow machine to start with, raising the CG without widening the stance can be more tippy.
Photos are from March 2018but will give you an idea of how they look on the P-5
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