Just to warn you, these have a tendency to sell out. Once that happens, the only way you'll get the title is on the secondary market, and I can guarantee you that it won't be cheaper (unless the book is just ruined).
If you can swing $40 every 6-8 weeks, then it's a good deal with almost immediate value accrual.
Foer's signed first editions average in the $100-$200 range (with a few breaking the $1,000 mark). It's also worth noting that Indiespensable titles seldom sell for less than $50 on the secondary market and many titles are valued much higher. Check out the listings on Abebooks to get an idea.
Here I Am has gotten a starred, boxed review from Booklist and a starred review from Publishers Weekly.
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