Ugh. Everyone is right when it comes to babies. Apparently.
Only YOU know what YOU do with your son, they don't. They're not there 24/7, are they? YOU know YOUR own son more than anyone else does.
What works for one baby might not work for another which I think is why there's so many conflicting opinions.
I just wish some people would keep their noses out unless they think that what you could do actually did work for them. If not, then I expect them to not get all arsey when they're ignored. They had/have their own kids, it's your turn now.
From the day my son was born, both my sisters and mum had something to say. My mum had 5, so I listened to her more (even if she conflicted the midwife). She talked sense when it came to parenting, but my older sister... still hasn't stopped even though she doesn't have a leg to stand on. I think she's just insecure because she has so much trouble from hers and she's a hypocrite. The most annoying was when she and my mum got out all my son's clothes because they thought "they don't fit him, why have you still got them?" - I had recently gone through his clothes and bagged the ones that didn't fit. He was an early baby (soon shot up!) so I didn't hide the fact it pissed me off whilst hanging them all back up again, like I was a dumb fuck or something!
Tell them to piss off and shut up. 
If you want their advice, then tell them you will ask for their "sought after" advice.