Sure you can use Goomba Color, but using emulation kind of defeats the purpose of flashcarts, playing on the real hardware (emulators aren't that accurate). I don't think Goomba Color supports linking either.
I prefer to use the EverdriveGB, but there are some advantages to using Goomba (not Color). You can colorize games, there are tons of palettes to choose from, and one palette that you can customize per game. There's partial-to-good Super Game Boy support, depending on the game. There's support for custom borders, and some games play kind of okay with borders disabled. It's a lot faster to switch between games.
And most importantly, save state support is great for all of those early games that didn't offer quicksaves, only gave you passwords, or just plain didn't let you save at all.
Goomba Color, on the other hand, I'm not sure if there's much benefit there. I guess you could run the Zelda Oracle games on a backlit GBA without GBA mode enabled, so the color palette doesn't wash out. I think there were a couple monochrome games that were less buggy in it, but a lot of Color games just don't run fast enough. EDGB would definitely be better for most Color games.
I think there was an older version of Goomba that had link support, but I'm not so sure.
build quality is pretty cheap and if you like at the pcb you just know it's not gonna last very long...
I don't know about
microSD, but I have an original EZIV with
miniSD support, and that thing runs as good as the day I bought it, probably a decade ago.
It's tried to "brick" on me a couple of times, but I just rebooted the firmware and it came right back to life.
Man, if you guys are just going to throw your EZ Flashes in the garbage, I'll gladly take them off your hands.