I'd like to know if anyone has read or used both books and, if so, which do they think has more to offer an art student. My friend is also looking into them so we'd greatly appreciate any and all advice before we fork out money for either of them.
They are both very good. I'd say John Raynes is the most technical. It has sections and exercises you can follow, and they are rated according to difficulty. Like anatomy it's always interesting to see how different artists approach the problems. You buy one and your friend the other, then swap and see how they compare
It's a solid book, but this is a case of the writer's knowledge far outstrips his abilities as an artist. Despite a pretty well organised how-to on as much reference as most comic artists (it's primary focus) will ever need, the example artwork itself leaves much to be desired. A better inker and colourist may have sharpened up the presentation considerably, but wouldn't have been able to do much about the occasional error in anatomy.
If you can get past the presentation, this is a good book to add to a perspective library.
Like with figure drawing books, getting a bunch of perspective books to get different opinions is always a good idea. Your local library should have a few. That said, "Perspective made easy" by Norling is very cheap, and covers everything you need to know in a clear, well drawn and understandable way.