Documents to go is WAY too expensive. It's 69, BUT it's often on special, right now they have it for 49. Still too much in my opinion. I've seen it as low as 29, I MIGHT go for that, but I don't need it's goodness that much.
You should just be able to open it right from your phone without any extra apps. All I did was send an email to myself with the .pdf in question as an attachment and when I received it, I opened it and was able to instantly read it.
Emailing is a way to go for small files, but for larger files get the D2G upgrade. If you want to hunt with the big dogs, you need the best tools! Doctor Neutron