Yeah, perhaps a bit of lag but the upside is that they deliver a constant supply of mixture with no flat spots. Because they rely solely on vacuum (aside from throttle input) they're less forgiving to any vacuum leakage than what you may be used to. Because they have no accelerator pump getting the choke(s)to work for starting purposes is important too. Once you get them dialed in, it's "set it and forget it". Best of luck.