I'd say its hard to classify 'best aerial' when they both cover different ranges.
Either way, they are extremely complementary to eachother and both would suffer without the other. I really like falling and dropping uairs as an aerial trap, especially when i still have my double jump. If they airdodge the tornado, I slap them with another tornado, or double jump bair. The mixup between all of these means they are never safe. I truly believe it is an area we have a huge potential in, megaman is currently seen as a low risk low reward in neutral character... But if we add horizontal pressure by expanding our gimp and ledge pressure game, and add huge reward vertically by improving our airshooter and bair juggles, he could become a low risk high reward character, which is historically super powerful in smash.
Anyways, I thought I noticed myself getting more clutch uair kills than normal, but just chalked it up to using the move more. It seems to benefit heavily with rage (most windbox/multihitbox moves really do) and this is wonderful for clutch situations, comebacks, or sealing an early victory when they get greedy and try and fight you high up.