If the fares are the same then EK is the no-brainer here. SimplyAviation (a popular TripReport resource) reviewing EY from LAX > SIN (via AUH) and found the catering to be quite lack lustre. Here's what a meal in economy looked like during the trip:
I have had far better meals (at least in terms of quantity) on UA in Basic Economy long haul than this. In addition, they've appeared to have moved to a buy on board menu for most items you would normally get these days including deserts and snacks. He also mentioned during the report that they may be short staffing their cabin crew. In particular, he mentioned that they only had one flight attendant per aisle serving meals (normally there are two) which significantly slowed down the on-board catering (first meal was served in 2 hours which while not the slowest seems a bit outside the ME3 standards).
You have not reported where you are travelling from which would also dictate what airline options are available to you.
Here's the video TripReport:
Safe Travels,
James