It really all comes down to what type of company they want to be and how long they want to be in the market. They may be a flash in the pan in which case it will likely never get expanded features or updated for new 3DS firmware. If this happens then it is what it is which is a temporary solution that will let you play a large library that is out now without updating past 5.1.x......If they want to keep selling the thing then they have thought ahead and it will have some flash capability either thru a file on the sdcard, a usb trigger cable (like m3), or a usb flash dongle for the PC. Won't matter because no matter what gateway does (flash in the pan or better) other better known and established companies will reverse engineer it and make an improved/cheaper product. If there is never a true 3DS crack then I could very well see Supercard or another established company making some type of 3DS/DS card that you could play both roms, us DS mode for homebrew and a 3DS save/rom managing application or OS.
I ordered gateway and I think with the number of 'known' and fairly reputable mod suppliers that are offering this thing there is a pretty good chance it is real and will make it to market. It is interesting that they are teasing feature like upgradeability, 6.x compatibility and save/restore functionality. Why not just come clean and leak or tell us what it can do? Usually when companies obscure its because they don't want to tell you its limitations and want people preodering before they let them down. A few more weeks and all will be known.
I'll be all over the Supercard version when it inevitably appears. Safe to say I won't be updating my 3DS firmware for a while anyway, will wait and see how this Gateway thing turns out though.