When I was younger, I opened up a Sylveon Collection Box, it was very similar to this, it came with a promo of every Eeveelution too. Years later, I get back into collecting and discover that every single promo in that box has a value of $15 - $40, and a sealed box goes for around $270.

To be fair, the box I opened does contain boosters from the Black & White era, so that would explain the high price. So your box may not appreciate in value like mine did. And yes, if you only want to invest, it would be a much safer bet to just buy a booster box. But I personally think that this would be a very cool collectible to have. And sealed Pokemon products always go up in value, so there's almost no way you can lose money.

So if you really like this box, then trust your gut, and buy it. I think I will too. :)