With the help of Ksplice the Ubuntu Server droplet has achieved 555 and 401 days uptime without downtime (could hang on a bit longer but later decided to reboot once every 3 months to address security concerns).
DO support has been responsive and friendly, DO keeps (slowly) delivering new features such as private network, Load Balacer etc. For existing $5/m DO users, I don't think it's worth the hassle to migrate to Linode (or Amazon Lightsail), the performance difference will be unnoticeable for most people's use cases (personal web hosting, strongSwan based IPsec VPN, etc.).
A good reference: https://joshtronic.com/2016/12/01/ten-dollar-showdown-linode...
Will provide the feedback to DO and see if they can match the Linode offer (I am sure they will do something).