"Firstly, I am thoroughly enjoying and benefiting enormously from the service. It is wonderfully educational, full of real jewels of information and advice, and has already improved my investing.

"Question: have you ever read / reviewed Joel Greenblatt's "Little Book That Beats the Market"? If so, I would be interested to get your thoughts. The back testing results http://www.magicformulainvesting.com/news.html?newsid=20100419 are impressive considering the performance of the S&P 500 in the last 10 years. I am very tempted to apportion some of my capital to this system but am a little concerned by the long term (3 years) outlook for U.S. equities."

David Fuller's view Many thanks; I am delighted that you are benefiting from the service but of course any investment success is due to your own decisions.

I am usually the last person to hear of a new investment book or service and that is true in this instance as well. I hope it is helpful but anything called "magic formula investing" raises my suspicion. Also, I would be wary of back tested results but if you can monitor it in real time through a market cycle, that would be revealing.