Dildo Progression

[boytoy84]

I've seen several teases and faproulets that use words like "medium," "large," or "huge" when talking about the size of dildo to use. So I'm wondering what sizes everyone uses in these cases.

I personally have used a 1.5" diameter dildo for medium and a 2" diameter dildo for large. After taking the large the small seems so small though. Does anyone else use a different scale?