Next time:
http://www.walmart.com/ip/Campbell-Hausfeld-TL140200AV-1-2-Composite-Twin-Hammer-Impact-Wrench-Wrench/38206491
Mehhhh
McMaster Carr long allen keys, a couple pieces of iron pipe, and a bfh.... or, a good deadblow plastic mallet.... fixes many more things, and can be multi tasked.... and ya don't need a compressor.... well, you DO, but not for removing bolts.
And if you do buy an impact wrench, buy a good one, and buy an ELECTRIC one... low powered compressors, ain't gonna drive a wrench like that properly...
Use discretion when buying tools.... a hammer and some simple add ons break bolts free in one whack, and you will likely never abuse the head of the bolt/fastener like you will with an impact wrench