I printed the smaller one of the thomas helmets (version 1.0) and the guy man scaled down by 10%. This is in my opinion the right size for it, i did the whole guy in normal size first and it looked comically big (even though i am a tall guy with a relatively big head).
Yeay, I'm done. It took a lot of work - and I messed up the paintjob on both of them :C - but they're done. They still turned out really well IMO