I've been using NordVPN for a few weeks now and I don't understand all the 1-star reviews. I haven't had any problems with the service so far.
When I start my browser it takes a few seconds for the VPN to connect, after that everything works fine. Some speed tests have shown that my download doesn't change much, but the upload is currently three times as big with VPN as without (according to the contract it should always be as high as with the VPN).