i found it nice , smooth  with logical romance development story between the two main leads
but i found their romance also lame & lukewarm one & that bothered me alot cause i found the story at the beginning was really promising
AND
as usual the weakest point ever at any KD  is the ( END ) very few dramas that really ended the drama strongly & satisfied me

SPOILER
> > > > > >

i found many things that provoked me much

1st
how can ( Lee Dong Wook ) asked ( Lee Shi Young) to trust him while his actions towards his EX was weird
till the end it appears that he loved his ex comparable to the care he gave to lee shi
he didn't even try to hug her after rescuing her from drowning  
it's very normal & spontaneous reaction towards the one u love when he/she  became in danger  u can't control it  
he didn't even show her his face at the hospital while she was fainted
he didn't even try to convince her with his true  love  he only said i'll leave u to think
he left  a suspicious woman to THINK !!!  ... WHAT THE HELL !!  >_<
she had all the rights to doubt that he is loving  her  

2nd
i despise   lee shi father so  how can he still loves a woman cheated & left him for another man  

3rd
i found that  lee dong friend  ( oh man )  at the last ep  his behavior was shocking  he exceeded so much to protect his wife as if killing lee dong was the only solution  
this was really insane & nonsense,  the writer was mad & provoked me so

4th
i found the character of  jessica  ( lee dong EX ) was so provoking & selfish  not honest & pure as they said at the drama
what crosses her mind she do  it  right- away
she did whatever she wants  Without consideration to anyone
her demands should be done immediately
her character to me was really annoying