Keep an eye out for when they do beta tests of exams. You'll get the cert for dirt cheap if you pass - we're talking £50.
There are two catches. The first is that some of the materials won't be covered in the existing books - the point of these is to update the contents. They do tell you the basic tech that will be covered though. If you have a solid understanding of them, you'll be fine.
The second is that you will be waiting MONTHS to get your result. I believe they wait until the exam you tested goes hold before giving you the cert. Last time, I waited something stupid like 6 months.