Tried it last month and comparing it with the former Setagaya I would say:
broth was equally nice
Hakata's pork was better
Setagaya's noodles were better
Oyakodon was equally nice but Setagaya would include some tasty pickles on the side
Overall, can't compare with Ippudo (neither could Setagaya) but I'm not overly distraught that Setagaya is no more - Hakata is a decent enough replacement.