If you are one of my students, I don't feel comfortable pressurizing you to get my book at all, because that is undue influence, and unethical! But there is a way out of this dilemma. Visit your local public library. There you can borrow a copy for free, and I see that many libraries are now getting it.
Don't you love the library? So often we forget it exists! Support your local library!
I hope that helps!