99% of those XXX in one ds carts all over Ebay are actually Ace3ds+ flashcards with the sticker replaced, and they mostly work. Just copy the ace3ds kernel to your sdcard, and swap. They have no time bomb.
If you somehow get one that's not, and it seems to have the timebomb, then get ysmenu from retrogamefan thread, and use that.
As long as they are formatted properly, 64 and 128 gig sdcards will work. Windows doesn't like to format them properly.
The "official Panasonic sdcard formatter" is a good choice except that it won't format past 32 gb as fat32 either, and will insist on exFAT, which won't work.. i think people usually use guiformat to format their 64 and 128 gig scdards.
but the official formatter tends to make sdcards load faster, which matters for games like Metroid Prime Pinball.
ANY current r4isdhc.com and r4i-sdhc.com cart will have a timebomb. the actual r4i gold cards say r4ids.cn on them. they are NOT actually colored gold. they also do NOT have a year on them.
If the menu look like this it HAS a time bomb.
There are a few r4i-sdhc.com carts that do not have a time bomb. the oldest ones that don't support 1.85b DO support 1.12d which is free of timebomb (the team realized the newer firmware wouldn't work so they released a "final" non time-bomb firmware for that cart.
No idea if they will release 1.85c