Kezo the 55 inch Hisense E7H is now just £349 at Costco but alas 55 inch really is to big !
Personally no I watch a 55″ and I sit closer to the TV than you, as my room layout is different to yours. I guess youd need the £22 stand from Amazon.
Its length is 4″ longer than the 50″ so 2″ either side to centre it in your corner.
Its also very easy to return to costco within 90 days.
My viewpoint is if you want a midrange TV at the price with 5yr guarantee you cannot go wrong!
Did I not show SD and HD content in the videos of the TV as I normally like to do this? Have another look 🙂