I think that is the problem any time you try to drive a LED too hard. If they would back off the power a little these things should last forever. Just add a few more LEDs with a little less current in each of them.
Sort of a "pay me now or pay me later" situation.
LEDs are one thing that should keep getting cheaper as they go. The whole "blue LED" (the way they get white) concept is really not that old. Red and green LEDs (a much older technology) are dirt cheap.
