I'm in the LAX F lounge on average twice a month. Never have had an issue with service. There are instances where I don't have enough time to enjoy sit a down meal, especially if I'm flying out of T4/5/Eagle, so I will hit up the AA Flagship lounge. I find it to have more varied options than the LAX OW J lounge.
In MEL, I'd definitely avoid the windowless Business lounge.
That said, it would be nice for the F lounges to have a few more self serve options out all of the time. LAX does put out cheese/charcuterie on busy nights, but wish they did a bit more regularly.