One big negative about the mini nes shit is the length of the cable on the pad is ridiculously short. And obviously it's overpriced if you compare to like normal emulation, but I guess you can say you pay for the packaging mostly, the pad especially is nice, even with its tiny cable.
I wouldn't buy one though, I still have a NES and while I'm fairly sure the batteries in my Zelda cartridge are probably dead, I replayed the game a while ago already(I mean it was probably 10years ago now, but it was recent compared to when I originally played it). And I'd say Zelda is literally the only game I'd bother playing on NES. SNES games, there's dozens I'd want to play, but NES, there's only a few and the only one I'd want to replay is Zelda. Maybe Mario, but meh.