Just a heads up about the Specialized sale.
There are both new and old Purgatory tread designs on offer. Newer is reported to be way better in every way – old chevron tread design has been radically changed to more widely spaced knobs and more aggressive side knobs with a squared off profile. It’s not a subtle redesign.
old version was fine as a rear on unchallenging trail centres, but was useless on anything vaguely steep, techy or loose. New one looks much more useful as a faster rolling rear for harder use, or could make a fast rolling less aggressive front. Just make sure which one you’re buying.