For me, Diarrhea's assessment is SPOT on! The Epon 460 driver is shorter and significantly less forgiving than most drivers I've tried. I am currently playing the TM 460 and it's absolutely longer and more forgiving. Contrary to popular belief, I've been told (by clubmakers) that Japanese drivers tend to have very small sweet spot. Although I wanted to love the Epon (investing heavily on a reshaft) it just didn't work. I had my worst driving stint with the Epon. I'm finally coming out of my slump with the TM. This is not to say that the results will be different for others.
On the other hand, the Epon 3 wood is a different story. Long and forgiving. I was this close to giving up on Epon products but the more and more I hit the 3 wood the more and more I like it. I never thought that my TM 16* wood would come out of the bag but right now I'm going with the Epon more often. I don't even have to hit it well to get great results, it's amazing.
Haven't tried the irons so can't say. I still have my Epon Copper X-Wedge 52* and like it, but it's got major competition with the TM Y Cutter.