Yeah but that's the problem... I don't want a special mystery Dell ISO, I want to use stock Ubuntu and have it Just Work. Using Dell's ISO locks you in to that

Yeah but that's the problem... I don't want a special mystery Dell ISO, I want to use stock Ubuntu and have it Just Work. Using Dell's ISO locks you in to that certain image (upgrades are very likely dependent on Dell), it locks you in to Dell support (good luck posting in the Ubuntu forums about your super-special Dell ISO), and it almost certainly means they're not contributing back to the OSS community (though that's not so much a pain point as it is a general gripe).