It's easy to use, it has all of my accounting software needs - in one place! I like that they are always adding new features which makes them more useful every year or so for me as an accountant/bookkeeper with multiple clients who uses their services regularly (e-filing taxes each quarter is great!).
The customer service can be slow at times but nothing too major there either unless you're not using your account manager very well then maybe just ask questions instead if needed help faster than usual? Easy access from anywhere since everything we do online now days anyways through our laptops etcetera; no need get up out bed when needing some quick assistance especially during tax season!!