I've read other posts where users say they don't like capacitive buttons, but they never say why. I'd really like to know what the objection is.
Until I tried them I didn't have an opinion. Now that they're on my Nexus 5... I prefer them far and away better than the home button on my Galaxy models.
Being virtual there's nothing to fail, no way for moisture to get in and they're lightning fast since there isn't any physical travel to press down. I just don't see a downside. Especially considering the touch screen is capacitive.
Finally when scrolling or reading they are hidden which gives more display area.
Your feedback is appreciated