Getting into tri's i was caught in the gear frenzy and purchased a time trial helmet looking like a space suit hoping to bike up some speed savings to compensate for crappy legs.

Now a few years later my old helmet is calling for a replacement and I need help to choose. I have improved and now post front of the pack bike splits so this time i actually want real aero benefits.

Although i am kind of tired of the space ship look and i have started to contemplate how large the benefits actually are. Especially since I am not strong enough to keep optimal neck position for a full IM.

- How large is the difference of aero road helmets vs compact TT helmets vs spaceship TT helmets?
- What data source is recomemded to campare helmet drag?
- Your favorite helmet?
- Other relevant input?