Brightness is just one of the HDR parameters and I would argue it is the less significant one. Contrast and black level are much more important IMO.Borrowing from photography, there dynamic range is measured in stops (each stop - double the light amount). This maps directly to contrast. Human eye can distinguish 10-14 stops in a static image (dynamically, more than that). Converting to contrast, that is 1:1024 to 1:16384.TN or IPS panels can have - and today, usually do have - contrast of 1:1000 (10 stops).VA panels can do even 1:5000 (as demonstrated by some models) and pretty commonly do 1:3000 (11.5 stops) like this Benq.Black levels are much more variable based on panel and monitor quality (and target audience) but low black level is easier to achieve on VA panel. There is a reason most TV-s are VA ;)FALD can help somewhat with contrast but it usually has downsides, primarily haloing even with many zones.I have an illustrative picture of black levels.From left to right: LG OLED TV, Asus PG279Q (a bad IPS), Eizo EV2736W (a good PLS)Monitors are not actually calibrated but are configured to be similar and brightness-wise around 120cd. TV is set to be much brighter. Image on all screens is the same - black test from Eizo Monitor Test OLED... does not have a contrast rating due to zero black level. And it shows. In addition to all the positives, also negatives - especially the issues with near-black tones. Generally that is not a problem with the display itself but content which does nto account for such dynamic range. HDR content on a capable screen definitely needs to be 10-bit, if not 12-bit. And this is really not specific to OLED but any actually capable HDR screen.Back to the topic - 300cd really is not the concern. That is enough for most use cases (I would say even with HDR). 1:3000 on the other hand makes it better than many other "HDR" monitors. It will not really have the wow factor of HDR though, HDR on these remains a marketing gimmick.