Hi
I've used United from Edinburgh via Newark for the last 12 years and never had an issue with them unlike BA via Gatwick and Virgin via Gatwick , both bad experiences.
In the last few years they have upgraded their in-flight entertainment and it makes the flight a breeze for me. Loads of channels and stop start when you like makes the flight fly past.
Food wise , again no complaints , it is airline food and gets the job done. They have like most US internal flights cut back on the offerings there. Used to get a nice sandwich or ice cream bar down from Newark but now they just try and sell you a box meal.
Still next trip in 2017 we will be on United again no questions.