You should always be 110% honest about everything and anything when you speak. At least, that is what I think. I get it from my dad but I am personally extremely honest and blunt about everything. I do not have a filter that stops me from saying something I should not, that filter only turns on once in a blue moon. What is the point of giving any false opinions?
People that I keep close to me, family, and friends know that I say what is on my mind. My immediate family is used to me because I get it from them! We are extremely honest. Others may be taken aback for a second but my words are humorous so it isn't so bad. If you are also a blunt person, you know that you get the two-second thought of- "hm, maybe I should have waited until I knew this person a little while longer to say that." This goes away quite quickly.
I feel that being honest with someone you have known for ten minutes or your whole life is so important. Although I sit back and observe people I am meeting for the first time, I'm upfront in our conversation because it doesn't waste any time. They adapt to my personality and quick wit which allows me to tell if they can handle it. A lot of people get easily offended which is the complete opposite of me. Some may take serious offense to what you think of as a small criticism, but to them- that should not even be spoken of.
When I do not like something, I lay it out and it's handled. I have had people tell me to take it down a notch or to adjust my approach when dealing with different people. I do not believe in that, take it or leave it. Honesty is the best policy. Tell me your expectations and vice versa. This applies to everything- careers, friends, family, and relationships. It is beneficial for everyone, you will not be surprised by things people say or do. I believe that you should be surrounded by people who will tell you when that outfit isn't working, when you need to get your shit together, when that guy or girl you are talking to is no good, when you have toilet paper stuck to your shoe, and everything else.
Be the version of yourself that is not afraid to say how you feel, it should be normal! I always witness people who are afraid to give their opinion on something or stand up for themselves. Stay true to yourself and just be the person to help yourself or someone who needs it.