I've been thinking about the GoSmart200 myself, so a few questions for you...
1- While drawing, you manage to hold the same angle at all times?
If I understand you well, the idea is to make sure the whole disk/ring is constantly touching the screen 100%, right?
2- Any tapping noise while working?
3- Do you fear scratches on the glass or is the tip very trustworthy?
4- In which apps do you use the stylus?
1- Yes and no. More hand movement and stylus shifting is needed. The problem I get is that when drawing with a pencil you tend to place you hand and move your wrist to suit with pulling or pushing and pivoting left or right motions, with the gosmart you do more hand shifting as pivoting(benefit the adonit has) isn't possible. Two guys used it and one found the adjusting a bother while the other said it was minor and he could use it.
Yes the whole disc/ring has to touch the screen. It does have some give, very very minor though, so even if you don't get the angle 100% right when you press the remainder of the ring will touch. Note though that this is so far the most sensitive and least effort stylus I have used(bamboo & adonit pro).
2- I am a very light writer so no tapping for me, and the other users were cursive writers so I am yet to find out. Will check and get back to you later.
Edit: Yes it has a noise when I tap.
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3- I have on a screen protector but I have read some reviews saying it does. So far no scratches on my screen protector and so far no friction, stick or squeaks either, this stylus glides and is extremely fast and takes sometime getting use too in comparison to the slow bamboo and good paced adonit. maybe mine is well Teflon coated or just how it is supposed to be. So as far as trustworthiness without a screen protector, no, maybe about 65-75%.
4- Sketchbook, penultimate, noteshelf, notetaker hd, adobe ideas, myscrpit calculator, notesplus.
Hope this helps as this is my honest and unbiased view.
Any more questions feel free to ask, any pictures needed feel free to request.