The A+ (and Network+) are both have alot of varied questions. There is so much information on the exams that it is really difficult to study everything.
I was working for for a technology company on their helpdesk - way, way back in 1996. They handed me a stack of books weighing over 20lbs and said "All techs have 90 days to get their A+ of they're fired." That was just too much information to absorb in that time, but the thing about the A+ and Network+ exams is that while they cover many, many subjects, they do not go into much detail about a subject - unlike the Microsoft exams where they cover topics in great detail.
The question are general and for the most part, having a solid year of experience will make a huge difference. I took a few practice tests and found where I was lacking - back then (for me) I needed work on laser printers and DOS (yeah ... the OS portion was DOS and Windows 3.1). I just glanced over the portions that I knew and scored around 90% for both parts.
By the time I took the Network+ in 2006, I was in my 12th year in IT with over 6 years of networking. The main things I needed to study for that exam were Novell and cabling standards - nothing like having to memorize how far 50ohm coax cable will go (185m I think?
). Again, if you have a working knowledge of networks (IP, subnets, DNS, DHCP, etc) you won't have a huge problem.
Ultimately, the more experience you have the easier you'll find the CompTIA exams. Honestly take a practice exam (honestly meaning: one time and don't look up the answers or give yourself credit for someting you remember after you saw the answer - you'll only be doing yourself a disservice). Focus on the areas you didn't know well and review the areas you are more fimilar with as the exam approaches.
The Microsoft exams are completely different. If you have never taken one be prepared for some serious work. Years working with server 2003 made little difference when it came to having to know intricate, rarely used parts of Windows (i.e. backup, system monitor, etc).
Good Luck
- deneb