Received several mail offers for a DiscoverIt card, so I applied. Got a bait-and-switch response, raising my interest rate which I didn't care about because my goal is to build my credit so I pay off the card every month, no interest!
When I got approval, it was for $1200 with 682TU, 647EQ. 5 months later, I tried my luck with the "Request a credit limit increase" button on the website, and instantly got bumped to $1800. 2 months after that, Discover sends me an email telling me my limit rose again, to $2300. 3 months after that, I tried my luck again on the website, and my limit is now $3500! That button is great; no waiting, no calling, no hard pull (unless they say they need to, but haven't for me), just instant boost to my credit score by lowering utilization percentage (I pay it off monthly but my balance has been around $400/month).
They hard pull from Equifax, and the FICO score they give you is Transunion. To compare with CK score, that same month I was approved my FICO was 624. It's now 10 months later, my TU FICO is 669 (CK says 715), and I'm one happy camper, it's definitely my go-to card.
I also really like that they offer a true FICO score, which is more in-line with what real lenders use. Cap One had been using that model as well but recently changed to the fake one CK uses. It is consistently about 50-60 points under what CK says, but it's legit. I don't get my hopes as high thinking my score is as healthy as CK says, I'm still "fair" and it keeps me humble.