I have never tried an aero helmet before so I am looking for some input into what it's the correct fit. I took a picture of myself on the "aero" while in my bike, it looks to me like the tail of the helmet should be a lot closer to my back? Also it feels like the helmet it sitting a little high on my head? This Lazer Tadiz is a medium and I have a 58 cm "melon" so I am considering switching for a large and see if that makes a difference? Any Tardiz users out there are willing to give me any advice?
It does look like the helmet is sitting high on your head, but really there's no way to tell other than taking a trip to the wind tunnel what will produce the least drag.
I have the same helmet and looks like your fit is similar to mine. It could just be the placebo effect but I feel faster when I wear it and for the potential (probably marginal) watt savings of a different/better fitting aero helmet I'm sticking with the Lazer.