Which exchange for recurring buy?

For those of you that auto-buy BTC or other crypto, which exchange do you find best? In the US.

I'm talking set it and forget it (I know it's a bit more expensive than buying directly in Coinbase Advanced, etc.)

Coinbase: too expensive with 99¢ transaction fee for every purchase and a spread.

Robinhood: No transaction fee but paying higher price with the spread.

Fidelity: Not your coins and not transferable. But I'd trust Fidelity over any other exchange.

Other?

And yes, after enough accumulation I transfer to a cold wallet.

Thanks!