Unquote #29 answer

The quote

You either die a hero, or you live long enough to see yourself become the villain.

The puzzle as it was set

OQV AWFDAC YWA E DACQ, QC OQV XWJA XQPB APQVBD FQ TAA OQVCTAXZ LASQKA FDA JWXXEWP.

The key

Each code letter stood for one real letter (code letter, then the real letter it hid):

E → AL → BS → CY → DA → EZ → FB → GD → HW → IX → LK → MP → NQ → OC → RT → SF → TV → UJ → VO → Y

The most frequent code letter was A (12 times), which stood for E. Short words, apostrophes and repeated letters are the usual way in: a one-letter word is almost always A or I, and THE is the commonest three-letter word in English.