When I once one of the two varieties had there was virtually no difference observed firmly.
They are only minimally larger, most is not noticed that. (Sihe image: red = 17 mm white = 15 mm.)
The effort is the use of twice and to how it already who said kanns be with small Popillen, which can be seen inside the eye color.
From compatibility and supply is concerned everything was great!
All in all product and information providers are super and recommended, but I stick to the normal 15 mm lenses.
Therefore only 4 stars.