Not that great of a price when you can get a Sammy in the same size for probably $200 more.
I liken TCL to Olevia and Vizio. Both sold a lot of TVs because the quality was pretty good at lower line price levels.
Unfortunately, Olevia couldn't survive selling for that cheap. As for Vizio, they were the #1 selling TV brand for a while. Now that they have established themselves, their prices are in Samsung and Sony's ballpark. I saw a 55" Vizio for $899 at Wal Mart regular price. The Sony was $999. For $100 I'll go with the top tier brand.
For a 55 inch off brand, I'd expect it to be in the 500-600ish price range.