theoretically it may affect your credit scores; however, in my experience, it does not make a big difference. I've canceled a couple of credit cards, when I apply a mortgage, I still got a good rate.
not bad.4 U+ Q% @6 F4 i: G0 J" b; j# S
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but compared with other rewards cards, the rate of getting points is not good enough. But if you buy things a lot at their stores, it is very good.