Sony X800D is also very good. comes in 43 and 49.
http://www.bestbuy.com/site/searchpage.jsp?st=sony+x800d&_dyncharset=UTF-8&id=pcat17071&type=page&sc=Global&cp=1&nrp=&sp=&qp=&list=n&af=true&iht=y&usc=All+Categories&ks=960&keys=keys
two most recommended on http://www.rtings.com/tv are
Samsung KS8000
http://www.bestbuy.com/site/samsung-55-class-54-6-diag--led-2160p-smart-4k-ultra-hd-tv-with-high-dynamic-range-silver/5034800.p?skuId=5034800
LG OLED55B6P ...