When I first got the Intensity, I tried testing it on my hand, like Antipova did in her video review. I didn't think it would hurt, but it is uncomfortable, even on the first setting with lube.
There is no documentation on how to tell if the Intensity is functioning properly. I'm anxious about trying the Intensity for its intended purpose, because I'm concerned that it might also be uncomfortable/painful internally. I've read that estim is more likely to be painful externally than internally, which almost made me confident enough to try it, but I still can't bring myself to do it.
I know that the estim shouldn't cause any damage, but my vagina is one place I don't want to feel much discomfort. I've hesitated to make this post, because I'm pretty sure I'll like the feeling once I try it and it's kind of funny that I'm so nervous about a toy. Any advice?