I do believe Rayong (Ban Phe & Suan Wang Kaew) is better than Hua Hin. The price level is better for living. It means better value for money. When you buy or rent will you also get better value for money.
The beach is so much better. The beach in Hua Hin is not a place I want to see my children.
Hua Hin is better for restaurants but eastern seaboard and Rayong is a lot better for culture. Hua Hin does also win when we talk about golf.
I do life in Hua Hin at the moment but for vacation I go to Rayong. Maybe some day will I buy but at the moment just rent.