If in anything, than the PQ is surely what the HiMedia Pro Boxes doesn't have to be ashamed at all. For FHD and 4K fro sure. The SD, HD upscalling might could be a bit better, but it also compares well to other serious Boxes. The only thing i'm not so sure about is the color banding. Almost all Media Boxes out now suffer from some degree of banding. Also not 100% sure if HiMedia does proper native 10bit output processing, or just 8bit converted up to "fake" 10bit. These all can effect the PQ in various instances and degrees.
On my FHD SDR 8bit TV all the FHD+ videos look pretty good, no doubt about that. Sometimes I perceive some banding, mostly just on some studio logo animations and rarely also in a couple of darker scenes. Not sure tho' if it's just the source encoded this way, or the imperfection of the video engine. Also might could be the problem of some bad 8 or 10bit dithering method. But I would need deeper testing to be more sure about these. Also might could be the TV's dithering mismatch. Regardless, the overall PQ is still very pleasant.
No experience tho' how things would look on a decent real 10bit TV.