mybat: This is how I handle my very outspoken, but well-meaning, MIL.
I listen to her, and say, “I see your point”; “That makes sense”; “You may be right”; “That’s true”; “I hear what you are saying about that”; etc. I take her advice seriously, because she is an experienced, smart lady, and then I make my own decision on what to do.
I do not inform her if I am taking her advice – I just either do it or don’t. In general, I try to show her respect and appreciation, thank her for her input, but if what she says is not for me, I just do it the way I want. BTW, my MIL and I have a pretty good relationship (ba”h).
Hope that helps!