Hey Tia,
I realize that getting into a new format can be a bit daunting at first.
The Beginner's Guide is meant to take up where the owners manuals for consumer/prosumer machines leave off. I think if you take your time and read each post from the beginning things will become clear after a while.
Learning the basics such as the difference between the tracks on the tape and the tracks on the heads and how they interface is the only way to really understand which tapes will play with which heads.
Referring to the other post you made concerning head wear, the understanding of the above mentioned interface will also help you with that question. It may not tell you what you can expect as far as the hours that an A80's heads should last (I have no personal experience regarding that), but it will help you to be sure that your heads will last the maximum hours before needing re-lapping.
Of course, there are those who don't wish to know any of this stuff and that's fine.
But that's only a workable route to take if you have a tech who is familiar with your machine and can do regular maintenance and check ups for your machine.
Having a machine that's out of adjustment can ruin the tapes that you play on it and when it really comes down to it, it's all about the tapes IMHO.