Even the Vanguard retirement funds though have expense rations that are multiples of the underlying funds, assuming you have enough cash to qualify for admiral

Even the Vanguard retirement funds though have expense rations that are multiples of the underlying funds, assuming you have enough cash to qualify for admiral shares of the underlying funds. But you get automatic rebalancing and lower minimums. 0.15% is low enough though that I don't personally worry about the difference that I'm not saving by switching to manually investing in the underlying funds.