I've had this card for a year now and I've not had any issues. My credit score is up 200 points and it's amazing. The card itself is nothing fancy, takes a while to report so you have to be careful of when you carry a balance and when you pay it off, but once you get the hang of that it's easy. It also takes some time to update the balance before you can make a payment and after you make a payment so it's not for someone who intends to financially rely on it. I've never had to deal with customer service so I'm not sure how they are, but I'm not sure why I'd ever have to talk to them in the first place.
If you just need something to build your awful credit, this is the perfect card. If you're looking for something to be an actual credit card for financial stability or large purchases, this is not it.