I have the 55s405 2017 model and it is great.you can put a 32gb usb flash drive in tv and pause live tv for 90minutes remote gets a little sqeeky in a yr.The newer model for $50 more i would buy but when they 1st came out alot of reviews were problems with banding in picture.Basically i think the only difference is Dolby Vision.To get the best picture i think a 4k Blu-ray player would be good but i haven't purchased yet.The Hdr on the s405 only looks good on medium brightness setting.You need a least 25 mbps w/ internet provider to get 4k streaming.But true 4k would be with Blu-ray.Hope this helps.Also S405 65 inch 2017 model at Best buy sold out Thanksgiving for $399 so if you can get that what a bargain.Go to tcl.com they list stores and current prices.Thats how i puchaced mine Ipaid $379 no tax from Electronics Express.Good luck hope this helps.