Are the lounge options at LAX generally better for departing (and arriving) business class passengers?

How is the Polaris lounge at LAX in comparison to SFO?

For the itinerary I am booking, I have the option of UA Polaris or LH group, either via SFO or LAX. Departing via SFO gives me the option of the infamous Polaris lounge, the more sinister UA Club, or the Maple Leaf Lounge. Any other options at SFO?

For the return, LH group would be $500 less on the total ticket price, and arriving in LAX instead of SFO would be another $300 less. On arrival, do I get access to any lounge, given I have Star Gold status but only on business class (assuming I pick the LH group flight)?