Looking at the site they look exactly the same at the same price, so you may want to ask Rachio if there is any actual difference.
But assuming there are no difference except from being installed and supported by a company, choosing between the two is a very personal thing which depends on your personal financial needs and your feelings and ability for support.
If money is no issue, and you have no desire to take care of things, then going through a pro that will take a huge markup in hopes they will actually support you may be for you, so indulge yourself
Or else, save your money and take care of things yourself 