I love that when you get an email from someone, it goes directly into your inbox without having any other apps open in between! It's super easy for me as well since my work schedule makes scheduling very hard sometimes (especially with holidays). Nothing really - we haven't encountered anything yet haha but maybe because this software was made by our own team? The only downside would be if there were more people who had issues logging-in or getting their data straightened out so they could use all those features like segmenting lists etc.