sell the porsche and keep the m3 til the lease is over. As nice as Porsches are, they look very similar with only minor tweak each generation so you are not giving up much look and driving dynamic wise over the year (maybe). On the other hand, this is the last NA, V8 M3 (for the foreseeable future). might as well enjoy it while you have it. Can always pick up a newer/nicer porsche later with more high tech comfort features if that's what you like. just my .02.