Hey, interesting thread for gateway 3ds newcomers. I also just recently got a gateway after hearing about multi rom support and in spite of the bricking fiasco. But yeah don't really need emunand at the moment so just going with b1. There's plenty of other games to catch up on and fill in the time before the final version comes out, be it march or June or even later.
After following the steps to install b1 last night I tried to turn on GW mode after holding L + pressing Profile and the system froze... OOOhhh the little heart attack that gave me lol, knew it needed a hard shutdown/restart but still waited like 2 minutes waiting to see if it would correct itself.
After the reset it now boots into GW mode fine (without holding L when pressing profile). Now gonna look into how to switch ROMs on a single card.
Pretty impressed so far, even if the transition screens to GW mode are a little scary lol (coloured scanlines).