I think it´s good to say what you really think if you say things with a little tact.
I´m not the type of person to hold back, to keep things inside or to tell you I love your new hairstyle if I don´t.
Therefore some friends come and go and those who appreciate a good amount of honesty will be friends for life, for they can tell me exactly what they think, no matter how honest or straight forward they need to be.
Sometimes the truth hurts, to help you out finding another path in life, change your hairstyle or lose some weight.
I actually get annoyed with people who try to cover up any sort of criticism, trying to spare me instead of being honest.
If you are a confident person, you will learn to appreciate the value of truthful yet painful words.