Hi Stacy,
For what it is worth doing 80% is fairly good. The online exams also include the O/S too, so I don't really have an idea as to what you are truly getting on the hardware portions. However, that said, if it were me, I'd want to be scoring predominatley 90 - 100% on the online exams. The ten that I did on the APlus site were good exams I felt. I was scoring 100% on most of those exam when I took the A+ exam. Well, that's my two cents worth. Again though, I'd say, just don't stress over it all, and you'll do fine. The hardware exam is the less difficult of the two. At least that was my experience. Best wishes with whatever you decide, there is no right or wrong. You can do it, many others have.
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"If you don't stretch and grow, your 'status quo'."
"If you don't stretch and grow, your 'status quo'."