In regards to feedback. I mean, sure, this is a perfectly fine method of playing off region games on your system. The only thing is, if you own a big library this starts to get into the territory of owning a donor cartridge for every single game you want to play, unless you're prepared to keep swapping the back of the shell every time you want to change games. In some people's cases they might own a Japanese console, have 10 NTSC-U games but only 2 NTSC-J games, meaning they don't actually have enough donor backs for every game in their entire library.
But yeah, if you don't want to damage the console, hey why not. Personally I'm not bothered, consoles are reasonably inexpensive to find if you pick up generic models, and I'd rather cut the tabs away as opposed to risk damaging a cart like you mentioned, but whatever floats your boat!