That is good news although a tiny sample of one game each, but if it really has an edge I hope you can release that Blue Matter 451 soon. It would no doubt help not just me but all of us who struggle against those teams, ideally a specifically tweaked 343 to destroy United's rigid style of play if at all possible, but I would take any formation that can consistently create a good number of CCCs against them.
I already tried the other Blue Matter formations among others (100+ matches vs United in total) and against United they perform worse than Goodbye 343 Counter with AM/AP/SS which is probably the best tactic against top teams that I ever used in 13 years of playing FM. With pacey forwards it absolutely destroys attacking teams like City/Arsenal/Barca/Real/Bayern on the counter and is rock solid defensively, but like I said it has trouble breaking down an extremely narrow and defensive team like United whose fullbacks never go forward. I use it for all away games and at home against top sides, I usually concede only about 7 away goals in the league that way. Unfortunately that counter tactic doesn't create enough against smaller defensive teams at home so for those matches I use Demolisher (it performs better than WOF in my tests) which gives me more than 3 goals per game but is surprisingly solid and for me usually concedes only 1-2 home goals in the league all season.
But I definitely need a 3rd tactic to put in the 3rd slot to use against United and to a lesser extent Spurs, because they can easily ruin my whole season if I end up playing against them in cup finals on a neutral venue, which I often do.