I just signed up for and was approved for the Barclaycard. I also have a long-standing Cap 1 card...along with a Sapphire and some airline cards.
I use the Cap 1 for rental cars and non-brand local hotels, especially in Europe. It's never been a problem with coding. I plan to use the Barclaycard the same way. I was debating getting it...on top of the Cap 1...but liked the 40K bonus points and especially the 10% refund on redemption...which Cap 1 does not offer.
It's nice having those cards available for the occasional low-cost air deals that pop up now and then...<200 coast-to coast or <300 CA to Hawaii that are better than using airline miles. Good luck with your decision.