Go out and buy it. I guarantee you won't only read it once. It's not all that expensive, either.
Plus, I personally always found reading books (comics too) on the computer to be weird. I tried on an old Palm Pilot(OS4 I think, black and white screen), a PSP (Bookr for the win), and of course on my PC, and it always just seemed a little... off.
Edit: Turns out I had my receipt in the drawer beside me, cost all of $24.16 CAD at Chapters Indigo, after taxes.