A friend of mine used First Aid and nothing else and pulled a 190. He was just aiming to pass, so he was relieved, but that's a little too close for me. I haven't actually taken the test yet, but what I decided to do was use First Aid as more of a study guide and annotate it with info from other texts....it really isn't THAT bad, considering that a lot of the diagrams in First Aid don't make a lot of sense unless you know the info already. Well, I should qualify that by saying I've only done biochem, and had very little recollection of all the pathways, etc, so I had to supplement. Perhaps other sections are different.
Maybe if you hate the idea of using other books, you could try first aid and doing tons of qbank and other questions? Some people claim they studied almost solely by doing questions so maybe questions+FA=230?