Sure "10% Instant Savings NOW" sounds Great, but not if it drops your credit score...
Hard Inquiries Hurt Your Credit Score
While hard inquiries are necessary for certain financial actions, hard inquiries should be minimized as much as possible. Your credit score is penalized for multiple hard inquiries to discourage consumers from getting into too much debt at one time. Applying for too much credit may indicate that you are desperate for credit, or that you aren't able to qualify for credit. While one hard inquiry will "steal" a few points off your credit score, multiple hard inquiries in a short amount of time can cause significant damage to your score.
Keep your hard inquiries to one or two a year. Data shows that on average, consumers with lower numbers of hard credit inquiries have higher credit scores, which could save you much more than the temporary 10% for a small purchase, in comparison.
...“Then the Grinch thought of something he hadn't before! What if Christmas, he thought, doesn't come from a store. What if Christmas...perhaps...means a little bit more!”
― Dr. Seuss, How the Grinch Stole Christmas