Monitors for babies should have good video images that are clear and true to life, but they should also have quality sound that is easy to hear and clear enough that parents can quickly decide if they need to look at the viewing screen, go back to sleep, or get running to the nursery. So while you might consider video quality to be the most important metric for this kind of product, we rated both video and sound equally because, without one, the other doesn't much matter. If the sound is muffled, difficult to decipher, or not loud enough, then parents might miss baby's cries. If sound activation or thresholds for background noise don't work as described, then parents might lose sleep listening to a loud monitor. However, once alerted, you need a clear view of baby with enough details to determine baby's needs, day or night, or the video style monitor isn't much better than a sound only monitor.
If you struggle with technology and don't need or want to see your baby from any other location besides your home, you might want to stick with the dedicated monitors that require little setup and have fairly intuitive user interfaces. This isn't to say that most people can't sort out the Wi-Fi monitors, but it is undeniably less work to just plug the camera into an outlet and go than it is to sign up and download software applications.
It really depends on what you feel most comfortable with. There are audio monitors that allow you to listen to any noise coming from the nursery, vital monitors that track sleep and breathing and video monitors that add sight to sound. Babylist parents overwhelmingly choose video monitors. The security of seeing what your child is up to—like if they’ve gotten tangled in their swaddle, pulled their diaper off or climbed out of the crib—can be worth the extra cost of a video monitor.