I am not an expert in this particular field, but the surface models would also be my best guess, for a alternative to a more “professional” dedicated digitizer unit. Have you even researched if these digitizers can be had for affordable prices used?
I own the Hi13 model and I agree that it is too slow(too much delay) and imprecise for more serious use, like advanced drawing or painting. The real issue, to my knowledge, is lack of processing power in the tablet units. So, the more CPU power, the better the stylus performance should be. The Intel Celeron CPU’s is great in terms of low prices and having it run with a passive/fan-less cooler solution, making the tablet 100% silent. Plus battery life is extended. But in terms of sheer performance, you want something more powerful. Intel i3 equivalent CPU or better I suspect.
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