I have long had a Capital One bank account, even before I picked up this hobby, and also a Capital One 360 account (got a few small bonuses from that one). But I only got my first Capital One card a few months ago. The problem with Capital One cards is that they do a credit pull from all three credit bureaus, and they also have terrible customer service. I still applied for the Spark Business Card, using that $500 cash back offer for $4500 spend (the are offering $300 bonus now). They also have 2% cash back on all purchases, which makes the card valuable for everyday spending.
For personal cards though I haven’t yet seen any amazing offers that would be worth the three credit pulls. Doctor of Credit has a good article that might make it worth applying Capital One Venture card, by getting approved for two cards at once, thus combining the credit pulls. Travel Codex on the other side advises against it, but he’s focusing on personal cards.
Let us know what you think!