Krikzz' Everdrive line really are the only flashcarts you should be using on older consoles, they are premium. The cheap, Asian or Middle Eastern options can fry your system, they output too high of a voltage. The Everdrives will not damage any of your consoles and have the correct voltage, and have the best support and quality.
I was shocked I got an email at 5:30 a.m. in mid April saying the GBA Mini Everdrive was back in stock. I ordered it around 5:35, and when I clicked "pay", that was it, they were sold out after my order went through, I think I literally got the last one. Shipping was super quick, I'm in California.
The only complaint I have is the box for the Everdrive. Do not expect to get something like the Deluxe Editions from {{Redacted by EverdriveStore.com}}, these are just the Everdrive cartridges and a thin cardboard box. It just would've been very cool to be able to pay a bit more for a "deluxe" edition, with a proper Bit Box case with cover art, or a high quality cardboard box, a small instruction manual, and maybe a sticker or something, and maybe a cool official seal around the cartridge number(just a quality box that matches the very high quality of the actual Everdrive). You do get that cartridge number on the cart, and it's on a small white sticker on the box as well, so you can match the box to the proper numbered Everdrive.
Of course anyone able to get an Everdrive right now is lucky, while Ukraine is under attack. But if you prefer that cool golden serial number sticker and a manual with case, I'd wait for {{Redacted by EverdriveStore.com}} to get Everdrives back in stock. Otherwise, there is no difference, it's the same premium product as always.