It tried to revert to v2.0 and it is way faster than v3.0. Every action from adding to cart takes 2 seconds, while v2 is less than a second.
@cyrilnicko Can you give us some details that show that v2 is faster than v3? Upon our testing, both take less than a sec to add items to the cart. You can send us details to support@snipcart.com.