These aren't investments, they're games. That being said, I get what you mean about reselling, but ask yourself this:
If you are going to resell, and a lot of people aren't they just horde, do you really think the perspective buyer is going to care about this?
If you do believe they'll care, do you think that will really detract from the value you'll get? Remember, there are limited quantities and beggars can't be choosers...
Not mention, they're almost all like this anyway. A "flaw" isn't really a flaw if every cart has it. Perfection is bullshit, and impossible to maintain or ever achieve. Just enjoy your stuff and hopefully you'll find some value in it, instead of just becoming a curator for the item's next owner.
Okay. Just to offer my perspective on all this...
Firstly, I'm a games player. I own a home cart system and buy games for that system to play. I also like to keep them. I enjoy having a library of titles immediately at my fingertips. I'm not a completionist, so you won't see me with copies of Super Spy and Riding Hero on my shelves just to 'add' to what I have or to help 'complete' a collection. If anything, I find bloated collections the opposite; unsculpted, undefined and actual detracts from having an interesting selection of titles - regardless of volume.
I buy games to play them, but a byproduct of this hobby is that you end up amassing games you like, thus, the whole collecting aspect becomes involved.
I was lucky enough to get a copy of Fast Striker on home cart. First thing I did was have a look over the box art, flicked through the manual and fired that bad boy up. No messing. When I was done, I removed the cart, put it in the box and made a space for it on the shelf.
I didn't buy the game thinking of it as an investment. I still don't. I don't have any plans to sell it, ever tbh. I'm not suggesting it won't ever be sold, but I hope never to have to sell it. That's being realistic imo. The VERY same applies to all my other games I own. I bought them because I have a love of video games and the enjoyment and challenge they give me. Sometimes I resent the amount of money I have to outlay to acquire a game, but thinking about it's diminishable return or increase in value is never a big part of the equation for me. I won't deny though, that I am very aware that NeoGeo games hold their value over time, which makes the larger outlays seem less risky long-term, as I know that should I need to sell a game in the future, that I will most likely not lose a lot of money doing so and hopefully will at least break even.
£400 for one of these games (I believe) is actually MORE than what SNK were charging for official homecart releases back in the day. Nearly double. Simply, if my copy of my £400 game arrived with visual defections straight out of the box, I wouldn't be happy - looking to sell in the future or not. It's just the basic principle. personally, I like my belongings to be 'nice', but not necessarily perfect. All of my home carts (aside FS) are 2nd hand. All have insertion marks, fingerprints, some indents on some of the inserts, missing baggies etc. I don't mind as long as I enjoy them. They're 2nd hand after all. Like most here, I believe in playing my games but I also believe in respecting them and looking after them in a non-OCD realistic fashion.
This game is brand new and these defects shouldn't be present, even if said defects don't affect the desirability/future value of the item. Incidentally, the copies with the perfect inserts will undoutedly fetch a higher price in the future. You know what Euro sellers are like. They ask a fortune for shit copies and a bigger fortune for nicer copies
ev for a new insert and they said they'd send me one. But I'm afraid a new one will just get wrinkled again due to the case.
insertion marks 
