We all react in different ways to different foods - the only way to know (if you really want to eat the food) is to experiment and use your meter to check the effect. Personally I can eat about 80g (12.2g net carbs) of boiled sweet potato without issue. YMMV.
I rarely eat white potato as it tends to make my joints ache so if it's a choice between sweet potato and white potato, I'll take sweet potato because although it has higher carbs per gram than white, it has about the same effect on my BG without the after effect of joint pain.