WearTesters just did a review comparing both of them and the 5X is lighter due to not having the midfoot-cage. Same midsole, same upper, same outsole. Just a roughly .7-.8 ounce lighter.
@@LuisRamos-qw1gj decided to get the invincible 3's, which were the only ones I was able to try out in store. So I decided to go for 3's as they felt nice for the short amount of time I was able to try them out. Will get them on Thursday! Hope they'll work out long term as well, very excited to get my hands on them!