$3500+ for a backup sounds a little excessive... (IMO)

Why not use the one T2 to prepare audio files of your song repertoire, and use an inexpensive anything to lay down live parts at the gig if your T2 wigs out... A CD player or iPod is a LOT cheaper than a T2 (and let's face it, how often do you think it's going to crap out on you?)...

And if you GOTS to have an arranger backup, maybe save a few dollars and get an S900...

Still, must be nice to be making those incredible nursing home dollars and have two of everything!