<prompt> Human: A colleague of mine recently told me he applied to 5 credit cards all at the same time. He did this specifically for the sign-up bonusespoints and informed me you have to apply to them all at once so they dont see the various other credit checks. The cards have annual fees that are waived for the first year, and he plans on cancelling them before then.My specific question is: if I am on top of my finances and am not worried about 1 cancelling the cards, or 2 missing a payment, what are the downsides to doing this?For reference: Im 25, have excellent credit and dont plan on purchasing a home for at least 2 years.  <response>: Well, you might be interested in rchurning, since they do this kind of thing all the time.Swipe responsibly. 