LemonFoShoIt depends on what your usage is. These are entry-level open-back headphones and leak sound (google the difference between open vs closed headphones). The K553's being mainly closed, have much better low-end bass (the bass in the HE350's will sound super tiny, almost non-existent in comparison). If you are looking for open-back cans to pair with your K553's, I would go with the K7xx Massdrop Limited Edition - I have both.
Everyone saying this is a great deal but not sure if I should jump on this if its somewhat par