Well the PJ's are just as good if not better in mud the the MTR's atleast aorund here. I would think the Iroks would be better then either in the sloppy stuff. I don't run mud so I don't care. For snow and ice stuff the PJ's are the best tire for the job. I havn't heard much feedback on the iroks and snow, but what I have heard hasn't been spetacular. I like mine in rocks but only have seen on set of irks in the hills and they didn't impress me, the rocks where wet and the iroks just spun, of course the guy would air down any. The PJ's ride nice and are quite and will last about 40k. I like both but for everything I do(rocks,snow, DD,sand,baja,as little mud as possible) the PJ's are the better choice. oh and the sidewalls are super tough on the PJ's.