I like the back design a lot. I can even see an excellent way to mark the deck! 
Gaff cards - the most common are double backers and blank facers, with double backers leading by maybe two to one. A double backer that has one color on each side would not only be great for color-change tricks, but it would also make magicians that much more interested in owning both colors. You don't find those double backers very often with a deck, but they're mighty useful.
A possible gaff card set:
Red deck: Blank face (red back) and double backer (red/blue)
Blue deck: Blank face (blue back) and a duplicate of one of the cards, possibly a court card - useful for transposition tricks with a spectator-held card when you don't want to use jokers.
If you wanted to get more exotic, you can make trick-specific gaffs.
Thanks for the reply Don! what you mean by blank face is nothing on the card?
I guess ill go for the two colour ones so it persuades people buying both colours ahaha i posted a back of the teal colour updated above
A blank face card is exactly what it sounds like - a card with the normal back, and either a totally white face or, if your faces have a background design or theme in common, a face printed with the background only, no pips or indices.
A two-color double backer is good, but don't put it into both decks. That same red/blue card could be used in EITHER deck, getting a magician twice the mileage out of it!
Printing a duplicate of one of the other cards is something new that I've really enjoyed taking advantage of. The Blue Crown included it (accidentally, it seems!) with the Altruism deck, both regular and "Snow Owl" versions, and HOPC included it with their NOC deck in all five colors. In both cases, they used a queen of hearts.
There are tricks I do that really take advantage of two identical cards in a pack. However, in most decks, the only two identical cards you're likely to find will be the jokers - and even that's not always the case. People already expect a deck to have two jokers in it, but they don't usually expect a deck to have two Queens of Hearts!
Tested the two way back?? did you print them out or something? haha
Nope. Just flipped the image and compared it side by side to the normal one.
I'd be tempted to print out 52 of them if I had card stock. 
Then it's probably a good thing for you that there's a shop that sells the cardstock and many of the other tools needed to make homemade decks of cards!
http://www.lybrary.com/how-to-make-your-own-playing-cards-a-11.htmlThe site sells most of the specialized hardware, paper, and laminate which, when combined with some items you can find at a decent hardware or art supply store, will allow you to print cards, either standard or gaffed, from your home computer and turn them into cards that the average spectator would have a hard time telling apart from "the real deal" from USPC.
They also specialize in ebooks, and have a HUGE selection of PDFs of books on magic.
