According to numbers his performance in the test series is pretty much average. In the 3 matches he has scored 147 runs at an average of 24.5 at a strike rate of 41.29. His highest score was 62 which was the lone half century he made while he missed one by a whisker as he scored 48 runs in one of the innings. The numbers tell a confusing story as the pitches were tough to bat on and not many players scored too many runs in the series. But it will not be wrong to say that his performance was rather sultry. He showed problems against the rising ball, he was not fluent and he tends to poke at balls which could be suicidal in England. While in the absence of Sehwag he has no competition for his place in the team as Murali Vijay was worse than him but there are concerns whether he would be able to give India the head start against England. Nobody really seems content with Mukund in the opening slot but India has no other choice. Mukund did show some promise in 1 or 2 innings but he needs to learn to play the long innings quickly. A hundred on the WI tour could have given him immense confidence but he missed the opportunity and now India straightaway demands long innings from a new man on India's most important tour.
Technically Mukund looks sound but has some flaws which he needs to correct as early as possible. He needs to practice against the short balls as he would definitely encounter a lot of them from the likes of Tremlett, Anderson and Broad. He has to begin playing with soft hands and has to refrain himself from poking on balls outside the off-stump. He has the potential and can go on to score many runs in the 2 tests he might get to play. He would not be under pressure for his place as he knows he would be playing in only 2 tests but what he needs to do is to make himself the top choice for the opening slot in India's test team. Coming back to the question whether he was a hit or a flop in the recently concluded series, I would say he was rather a man of potential who let go his chances who is neither completely a flop nor a hit. The confusion persists and it remains to be seen what he does in England.