WWYD: Carseat situation

Jill

So it may be a bit long but bare with me. I had a Graco Click Connect from my daughter 2 years ago that was only used a handful of times, we kept it for just in case we had another and good thing we did because we had a surprise pregnancy lol. I took the cover off to wash it and get ready for new baby due in a couple weeks and noticed some damage to the styrofoam. Long story short, Graco is replacing the seat under warranty and I am expecting a brand new seat (same model we had) this week. It's compatible with the Sit and Stand stroller that we also already have. My dilemma lies here- my friend had a baby in December and her son is about to outgrow the Chicco Key Fit car seat that they have, so she really wants me to take it. That and the Chicco Bravo for 2 stroller, which my soon to be 2 year old would have to sit in the bench seat that she is too little for. Her car seat is not compatible with my stroller, but it's like a $300 carseat and one of the highest/best rated seats. So I have either a brand new Graco, or a gently used Chicco available. What would you do?