You would have zero concern. Because you have status. OP doesn't. He has all the reasons in the world to be concerned. Should something happen, he's not gonna have access to the premier line - he'll be on hold for two hours listening to the friendly skies spiel and waiting to speak to an agent.
OP, your friends are absolutely right. Avoid UA like plague until they get their act together. HA and VX are excellent choices to get to Hawaii from LAX; both are much better than UA in terms of service and reliability. AA is a decent choice. Inter-island flights are short and are actually fun.
let's clarify your "advice" a bit.
Do you recommend he fly Virgin America LAX to SFO, then Virgin America SFO to OGG, then overnight on Maui, then back to the airport the next morning for Hawaiian Airlines OGG to ITO?
Or, do you recommend he fly Virgin America LAX to SFO, then overnight at an SFO hotel, then fly Virgin America SFO to HNL, then fly Hawaiian Airlines HNL to ITO?
Just curious which 24+ hour VX route is better than 6 nonstop hours on a United 737-800 in first class for less than half the cost?