They're huge pieces of shit. I've had problems getting my food delivered on time almost everytime I order from them and they only give me half refunds.
I've only ever used DoorDash, but I'm trying not to. Not only is it an extravagant expense, these services hurt restaurants by taking 20-30% cuts of the sale.
Of course now with the pandemic, some are really relying on DoorDash and the others.