Phillip Reeve tested the lens and concluded:
Bad flare resistance can be a real deal breaker for a landscape lens as it has the potential to completely ruin your shots. Unfortunately many of the lenses from “new” manufacturers struggle a lot in this category, so I am really delighted to be able to list flare resistance in the “good” column here, which only rarely happens. Maybe NiSi has an advantage here by using the knowledge on coatings and light baffles they gathered making filters and filter holders before.
Now if you settled on the APS-C format to be able to use a smaller camera with smaller lenses you may very well be disappointed by the size of this lens, especially compared to the Laowa 9mm 2.8 APS-C. In terms of optical performance I do prefer the NiSi lens here though, especially because of its great flare resistance. So ultimately it is up to you, what is more important to you here.
You see it from the table, the good list is long, the not good list is short and there aren’t really things on it that will really get in the way, so what else is there left to say?