Done it twice on international layovers. It's definitely not worth the expense on a return leg, but on arrivals and especially on a couple hour layover it's well worth it for us. Both times were before the Salon and I wouldn't even consider the Salon now if I was traveling with my family.

It's great to just have a good meal waiting for you and not have to worry about your bags or transiting. Both times as well we've asked to have a meal boxed up for my wife and they accommodated that no problem. It was just waiting for us to pass through their private TSA on our way to the plane.

Now with kids I would probably rate PS even higher. Not having to lug stuff around the airport and search for food would be amazing. Also the outdoor area might be great to let them run around during the layover.

Dollar per hour or something this is a terrible deal, so if you're flinching at the price don't expect to come away thinking you got a steal. But the experience cannot be matched by anything else at LAX and it will certainly make your life easier and more comfortable during a layover or arrival.