1) A great platform for freelancers which can be used by other professionals such as accountants who work remotely 2) They have been very supportive of my needs 3) Easy interface 4) Great customer service 5) Excellent payment options (Paypal/Wire transfers).
There are some things about their site I dislike but nothing majorly so at this point they are still one of our go-to companies since we use them primarily through PayPaal anyway. Just make sure you get your invoice up front otherwise there could be issues getting paid fairly if not correctly! We needed an invoicing solution that didn't require in house support staff - also was looking into being able to integrate directly with QuickBooks via Zapier (since most clients prefer using QB's billing system instead of ours.) After doing quite bit research online and talking with several vendors, writeraccess seemed best.