when I'm shopping I usually look for 4 vrooms (I have found vibes TOO strong, but not many). Though I prefer a range of speed settings so I can decide in the moment!

At least three, or more.

I like 5 the most but not many toys are that strong so if it has at least 3 it's ok but the stronger the better for me.

I tend to use my stronger toys on the lower settings, at least externally. My favorite is the Little Steel Vanitas, which many reviewers rate at a 3 vrooms, so I voted 3.

It depends on the quality and the type of vibrations. I'm kind of picky because I can't use vibrations for extended periods of time regardless of strength. At first I just get super sensitive and after that I go numb, for lighter vibrations it just takes longer.

I like between four and five, any less and i can't really even feel it.