While the time noted may be a "legal" connection, there is never an absolute guarantee that things will run smoothly. I would suggest that 9 times out of 10, that connection would work. But if your inbound flight is delayed or there is a holdup at US immigration, US customs or outbound security screening, you might not make it. But if it is a legal connection, and booked as a connection on a single ticket, then you are "protected" and the airline will get you to your destination on the next available flight.
Personally, if there was another slightly later LAX departure option I would probably opt for it. But if the later flight was say 11am or later, I would take the offered connection and rely on being protected if I missed it due to late arrival of teh inbound LAX flight. Even with a 4-hour connection, if the inbound flight is 3 hours late then you are going to miss it. So how long is long enough? You cannot predict of your inbound flight will be on time.