I have recipes that need a fill of 2/3, some 3/4, and a very few that go almost to the top. I also use tulip liners for business and regular liners for schools, personal, etc. Because of this, I have every disher in every number. There is a number on the little arm that swings in the cup. I mark all of my recipes as to the fill number. Then based on the liner used, I use the appropriate disher (scoop) to get the exact fill.
Even on my micros and minis, I have a disher that will do the exact amount I need. I actually write the disher size next to the liner size (tulip, reg, mini, micro) so that I don't have to guess every time. Plus if you plan to expand with employeees if you are a business, the sizes help.
The best dishers I have found are from Sur La Table. They don't have every size. I fill in with OXO and ones from restaurant supply stores.
By now most of you know that I'm somewhat OCD about my baking. But this is a tip because I don't like wearing out my hands for no reason. In every place from SLT to the restaurant store, every disher in the pile will have a different amount of pressure needed to push the lever. I check for the easiest ones.
Also, if you use these for cookies (yes, perfect sizes there too), the ones from the restaurant supply stores will eventually break or twist, but they are the cheapest and only cookies like chocolate chip will break them.