Depends where you are looking at it from ! I built my main stand from the following fomula:
Sat on the settee, measured the hight of my eye - made the stand so that the water level was at eye level ! Job done, apart from its a pain to maintain as Im 6'4" and its EXACTLY the wrong height to work on... standing its too low, kneeling its too high !
I built mine 3ft high as its a good hight to look into plus it just sits a bit higher than the kitchen table so it sort of overlooks, really good to watch whilst eating dinner!!