The drama started well and I enjoyed watching it for the most part!
I think what bothered me is the fact that the focus of this drama changed after the first half approximately and became 99% focused on the love story. In the beginning Yoo Hyun Tae said that if he traveled to the future there must be a reason, I don't think the reason was to fall in love with some girl...
The music was really nice, be it the free style rap from Lee Ji Hoon or the old songs from J-2, they had a good potential to focus on music and make a story about all the family creating music together. It's a pity it went to waste just to focus on romance
Also I don' really like the female lead personality and I don't see a great chemistry with anyone so I don't think she deserves to end up with any of them.
Regardless it's still a nice drama, just a bit disappointing