not back, deck they were printed a while ago, but I can't seem to find them anymore
You're talking about the MagicMakers deck. Check some after-market sellers like bmpokerworld.com and the1eyedjack.com. They're limited and a collector's item but not outrageously expensive. eBay's a good place to check as well, and also Amazon.
If they don't handle any differently to the regular arcanes but are worth way more.... I'd keep them with intention to resell.
They USED to be better than standard Arcanes. They were E's first deck to use "performance coating". Same stuff every other card company calls "magic finish" on their decks. Now E is using them on most of their decks, eventually all of them.
I love breaking out a tax-stamp sealed deck of New Fans or Rider backs for a poker game. Adds an historical touch to the evening.
And yes, card games are the "intended purpose." 
I definitely agree, however as a magician, cards have a higher purpose than mere games and yes, as long as I have two of a deck I am willing to open one, especially when my magician friends with the Gold Arcanes will spend hours just passing the face cards around to be able to see them in person because they won't open their own deck.
If I have two of a deck, I'll open one, save one. If I have only one - I'll still open it! I want to see the cards in action rather than in a display case, sealed in the box and under shrink-wrap. If I didn't, I wouldn't have seen how beautiful the Broken Heart deck is. If I had only one Jerry's Nugget deck, I'd open it as well. How else would I know about this wonderful texture and feel these cards have, according to the magicians who've used them? Even with my saved decks, if my open deck gets trashed, I'd open the sealed. If it wasn't outrageously expensive, I'd probably try finding a replacement, assuming I was still interested in owning another pack.
I open at least one deck of whatever purchase I make and keep the rest sealed. This practice excludes decks like Jerry's.
Anyway, I remember using a deck of RJRTC's for a game of BS with friends. One of them persisted that she shuffle the cards. Oh god. Never let someone else handle your decks! I tend to forget that the only reason my cards (the ones I don't use for practice) are in such great condition is because I know how to handle them properly. Other people view them as items to use and abuse.
Even with magic or cardistry, I avoid doing any sort of performance with a nice deck because often time the response (with magic) is, "Cool! Let me see that!" or with cardistry people very often want to try a move themselves.
Spread awareness, teach people how to treat a deck correctly. 
I have one guy I work with, I can't hand him a stripper deck to shuffle. Instead of rotating half the deck along the horizontal axis into his other hand, he rotates them along the vertical axis - meaning he's turned around half the deck the opposite way before he shuffles!
I was using some cheaply-acquired casino decks I got when entertaining at the hospital for a long while, giving away the deck when I was finished. Two weeks ago I got the urge to try something different and packed some other decks. I did a trick for a kid with a pack of Tally's where he had to hold half the deck - and didn't realize until it was too late that he'd been eating fried chicken and didn't adequately clean his hands! One deck of Tally's down the tubes - I left them for him to play with since he greased them all up.
