Great attitude to have - it sounds like you'll be into the hobby for a long time and the vast majority of us here have bought at least 2, if not over 10, RIFs during the life of the hobby. So one bad gun won't be too much of a dent in your wallet.
Having said that if you're not using it for your first game, it's not too late to send it back if you did fancy taking a chance at finding a better RIF. Feel free to ask here for any recommendations either way - whether you return it now, or start looking for a new gun in the future!