If you can secure the car seat in the Burley, I'd go with that. The Bjorn might make it difficult for you to move around (turning around to see things passing you, etc., although maybe not an issue on a bike path) and might overbalance you while riding, plus if you DO tip over for whatever reason, the Burley stays safe and upright while a baby attached to you is vulnerable. I agree that the car seat in the Burley is no more dangerous than the car seat in a baby jogger.