They are the same.
750 is stronger than a 500 and than you have 10or10.5 and they are stronger than the 750 the 500 are not as strong
Hydrocodone is hydrocodone. However, all hydrocodone containing products in the US do have acetominophen in them as well.
Hydrocodone Polistirex is a time release formulation of hydrocodone bitartrate, used in the cough medicine Tussionex. Hydrocodone Bitartrate is simply an immediate release form. (ie Lortab)
Hydrocodone Bitartrate is merely a longer name of the Hydrocodone that is in the Hydrocodone/APAP preparation.