I think 442 is a gamble against a side of United's quality AND current form. As has already been stated, it's about what kind of tempo we adopt. 451 and a fast tempo.... and then the Yak is an option on the bench.
Too risky to play a 442 and if we concede early because the midfield is too lightweight then it may be too late to change things, once United get into their stride. United's strength is work-rate in midfield, and we should address it.