Third party brands? What's that mean?
Samsung and LG are about the only companies you're likely to come across that make their own panels. Companies like Asus, Acer, MSI, Dell, as well as AOC for that matter use panels by people like AU Optronics (AUO), Innolux, and recently Panda (no, for real, there's a company that makes panels called Panda and they're
rather good). As well as LG and Samsung panels.
Most monitors that are curved VA panels seem to be Samsung. MSI seem to use a lot of Samsung SVA in their products.
I'm no expert on who uses what
AOC is a
major player in the monitor market. They're not some Amazon/ebay only operation selling cut-price, low quality goods, and are a way bigger brand than people like Sceptre or EG. Not that brand size matters; EG have had some decent stuff. AOC are top-tier, same level as all the other big names.
AOC have a wide range of 1080p 144hz monitors (which I agree is what you're looking at assuming ~200£/$/€), including TN, curved VA, and IPS options. Some of them are quite popular like the
(VA, TN, IPS respectively)
But tbh, just about any monitor that's 1080p, 144hz,
and has freesync (which rules out a few older BenQ and Asus models still floating around) for around ~£200 would be fine