it depends what you do with the cards and most importantly how you handle them.
eventhough i do XCM, i could have a pack last me as long two to four months. just keep in mind magic's an art and your cards are your masterpeices...HANDLE them like they cost a million
having only one person handle the cards does wonders.
dont play poker with your performance deck !!
just use the older decks for your 'dirty deck'... doubles...card to poket/shoe/her bra (w.e your style is with beach magic)...practicing...or as i like to do sometimes with some spectators is leave the deck with them and add just sooo much more to your preformance. PLUS it cuts out on all the talk about your "fake deck" after you leave
-Eyman