My wife and I have one, our daughter just turned two. We are discussing if/when we want to start trying again. I've always wanted kids and have loved being a father so far, it's a truly incredible experience. Like pretty much any other truly great thing in life, it takes a lot out of you, it's hard but totally worth it, IMO.
To the OP - I can't tell you whether or not to have kids, obviously that's totally up to you, but I will tell you this - my wife's brother and his wife have three boys all under the age of five and honestly they are nuts. Super crazy, don't listen, all over the place, into everything, etc... I had a similar experience to you where we went on vacation together and it drove me crazy. My wife and I have made a choice to parent differently than them, we are more strict with our daughter (only to a degree so far since she's still pretty young) and believe me, it doesn't always work, but largely our daughter is well behaved and listens because we are as consistent with teaching her those things as we can be.
Also don't forget, things are a lot less crazy if you only have one kid, or have a couple spaced out a bit. Just something to keep in mind.