I have been studying the Mike Myers Passport A+ certification guide, and had heard that it was going to cover what i needed to pass the certification test, with little room for failure, no courses or anything else will be needed, so I guess my question is, will this book really cover enough, or should I invest in something else? Is a course really necessary? I can recognze components internally, set jumpers, troubleshoot softare and hardware, and I am pretty good at the logic of how and why. Any help?