If the slider have problems, if the wifi have problems and if the c-stick seems defective, I would say it's not a brand new one at all.
If you bought an used one, those problems should have been listed when you bought it (I bought a japanese 3DS with a defective cart slot but it was written on it, and as I know I could easily make it fixed, which I did, it wasn't a problem at all) and if they weren't, just show those problems to the store and ask for a refund/exchange.
Gateway just said they will work on making their new exploit works on older firmwares, so I assume they talk about 8.x.
Except if you really want a New 3DS, you can probably find a 3DS 4.5 for cheap in Japan. I got mine for less than 80 dollars (if you add the cart slot cost replacement, it make less than 100 dollars) on Yahoo Auctions which is pretty cheap as 4.5 start to become more rare.
New 3DS isn't really useful in my opinion, no to mention we don't even know if exclusive games will work with the gateway.
Nintendo just released this new version because of the patent violation of Seijiro Tomita, that's also why they also released the 2DS in the west before the 3DS (the easiest/quickest way to fix the problem was just to remove the 3D). And they probably added the "c-stick" just to make people believe the new version was really planned and not just a quick fix for the patent.
un peu plus d’un dollar pour chaque console vendue. Au total, Seijiro Tomita empoche donc 30,2 millions de dollars.
The guy got roughly one dollar for each 3DS sold, so approximatively 30 millions of dollars, and I suppose Nintendo also had to pay for further sells, which is why the 2DS/New 3DS reelases were required (avoiding the patent use and so, they don't have to still give money to him for the upcoming 3DS sells).