"Brick River has been a valuable partner for six years. Having an integrated website, email system, and registration system make the moving pieces of our communication plan work together seamlessly."
With most/all of your needs in one package, you don't have to sync systems together. Things are both easier and more powerful.
One site. 1,000 sites. No extra logins. Simply press a button and get another site. Tie them together - sharing layouts and content. If you're an agency, manage all your customers from one screen.
For good or bad, there aren't plugins on the Brick River system. The system is a collection of helpers and open code. So you have the coding flexibility to add in things that normally you would need a plugin for.
Brick River is up with just the push of a button. That means you don't have to wait to get going and you don't have code or hosting maintenance to deal with.
Brick River doesn't add any of its own transaction fees to registrations. It saves you lots of money and keeps you from feeling like you're being nickel and dimed.
Much of the same functionality as the big systems but less hassle. You're up and running right way - not in days or weeks. Just fire up an instance and get working.