I've used the site as a freelancer for 6 years (originally O desk). To begin with it felt supportive and despite the huge competition from freelancers charging barely anything and clients wanting ridiculous amounts of work for pittance I started to build up work. I had 1 issue with a client and the support team resolved it fairly and quickly.
Nowadays I'm constantly getting emails about ‘changes to their terms' which are usually not beneficial for freelancers. The ‘connects' system is the final straw for me. Upwork already takes 20% of all my earnings (they charge the client 10 or 20% too on the same work) now they want me pay a monthly fee to be allowed to apply for jobs that make them their money? It's no longer viable for me, I'll use my few free connects for occasional jobs but I feel a bit ripped off by Upwork.