I prefer Mogwai's more recent albums - Hardcore Will Never Die But You Will, and Rave Tapes - to their older stuff. But I've never been that into them, and I'm really not very interested in the "original" post-rock, the Godspeed You! Black Emperor, Mogwai, Tortoise, whatever stuff of the nineties. Ye olde post-rocke purists will disagree, but post-rock got great when Explosions in the Sky pointed it towards crescendocore and Isis pioneered post-metal.