Yeah... comparing a 2013 car to an unchanged-since-2008 car (Subaru folks would say unchanged since 2004...)
Sure the M135i is a pretty capable car, but the triple-LSD, user controlled center diff STI would eat it on a snow track. Or getting out of a snow bank after getting parked overnight in a snow storm. Pretty rare events for 99% of the people reading this thread, but here in Northern Canada, it may be worth it