I can only echo the sentiments of the other reviewers here, and I feel it's one of the best 10 quids I've ever spent.
I was pretty fluent in Excel prior to taking this course, but I was amazed at how many details and techniques I picked up. The individual lessons are short, to the point, and easy to understand and remember. Mike Smart has a talent for teaching, which makes learning a real pleasure.
One issue: the installation prog insists on putting the practice files in the C:\Practice folder, regardless of the destination chosen - although I admit I'm scraping the barrel to find any negatives whatsoever. To be fair there are none, and I regard this product as incredibly good value. Even before I'd finished this course, I downloaded the Expert level course (this isn't available on Amazon (yet?), but can be downloaded from Mike Smart's website).
My only disappointment is that Mike Smart hasn't created equivalent DVDs for Word, PowerPoint, Access, etc, etc.
Extremely highly recommended!