I wonder this too, hen figured it must depend on whether you make the diameter of the sizers the same, so that you get similar projection. Eg if you tied a stocking full of rice really tight it would be like a snooker ball and if you tied it really loose it would be like an actual implant.
I’m have a moderate plus implant so have wondered if mine project a bit too much as I think I’ve made them quite ‘narrow’.