I found a Lexar class 10 MicroSD 32GB card for $108 this weekend at Microcenter in Atlanta. I haven't had a chance to install it yet though. Planning on installing it and rooting it later this week.
How do you "wear out" a micro sd? I've got a 2 year + sandisk 8 gb class 4 that has seen more use than Jenna Jamison on a World Tour, and it still works perfectly.