Used s8 or new s9? - eviltoast

Hi all! I’m thinking of getting my first Apple Watch and was looking for some advice. I’d like to use the watch for telling time, exercise, health and receiving notifications. I’ve seen some used series 8s with good battery life and no scratches for a decent price (210-240). Would there be any benefits to getting a new series 9 instead? I’m hesitant because of the price jump but would love to hear your thoughts! Thanks!