I used mine right until it broke about 4 months ago, even at night DC 3 now 
I'm managing without it though. DC is loud enough to shout mummy never daddy if if they wake.
I'll be honest and say I was (and still am to a degree) a super anxious parent and liked to have it on whenever they were sleeping.
Having the technology to have them on screen to alert me of any unsettled moments-and it would be on constantly helped me, or fed the anxiety who knows but I felt better for it.
Maybe it took it breaking for me to realise I'd survive without it.