APS, APX, V0 and V2 - what's the deal?

I've been doing quite a lot of reading on this topic lately, and have emerged both enlightened and confused. Would anyone be able to clear up the following?

• APX > APS for quality, yet APS is preferred. Is this due to size?
• "--preset fast extreme" is apparently of inferior quality to "--preset extreme", yet is the one that is recommended. Is this due to efficiency? Is the difference negligible or outranked by the faster speed?
• On that note, does putting only "--alt-preset extreme" result in proper rips in EAC?
• If yes, then I've been told that "V0 --vbr-new" and "V2 --vbr-new" are actually superior to "--alt-preset extreme" and "--alt-preset standard", yet audiophiles continue to insist on APS and APX. What's the deal?
• Why is 320 CBR supposedly of the highest quality?

In addition to this, if anyone has any crash-course FAQs on MP3s, bit rates, quality, what all of the EAC commands actually mean (rather than just mindlessly following instructions on how to rip CDs), etc., that would be equally as awesome. Thanks in advance!

EDIT: Also, are copied CDs of lower quality? For example, borrowing a CD from a friend, burning it with the CD back-up function in Nero and returning the original and keeping the burnt copy for yourself. Are the EAC rips of the copied CD significantly worse off?

Jam it back in, in the dark.