Well, SFV has quite a bit of issues that are pretty nonsense according to threads/youtube/articles:
1) If you want to unlock characters, you need to earn money, if you want to earn money, you need to be able to connect to the servers but the servers are down. If you do the story mode and you are not connected to their servers, than you will not earn any money. Oh and you cannot grind money on story mode. It's a one time thing but people aren't sure whether or not playing offline "counts"
2) In order to unlock characters, you need $100,000 Zenny but if say you wanted a cool costume instead, those cost $40,000 Fight Money. I believe you earn $100,000 Fight Money per story mode quest but dont quote me on that
3) If you want to unlock a new character and you have 0 Zenny. You will need to WIN 2000 matches online or pay $6 per character. I believe SFV starts out with less characters than SFIV started out but don't quote me on that either.
Any many more!
https://www.youtube.com/watch?v=heIkAJ3qMDI
I personally wouldn't buy this nonsense ever but its up to you