Here's an update on this thread. I put this pic together to be added to the CRL's:

The top row is me.
The first pic is in my Jaing Skirata Version 1.0 armor. The helmet is a 1 piece Rubies Deluxe Jango Fett helmet. My chin hangs out of the bottom of the helmet and the helmet is far to narrow and short.
The second pic is me in my A'den 1.0 armor. It is the same armor as the Jaing set but highly modded and repainted. The helmet is a Don Post 95. The size is much better. It's close but no cigar. The helmet is still too narrow and although the chin is now covered, the back of my neck is exposed to accomplish this.
The third pic is me in my last upgrades prior to the SDCC upgrades. The helmet is a 1:1 Gypsyboy MOvie Sized helmet. The height width and length are correct for my body and armor type.
The bottom row is my brother.
The first pic is his Mereel Skirata Verison 1.0 armor. The helmet is a Rubies 1 piece Deluxe Boba Fett. The armor itself is subpar but, the helmet is clearly to small. Too narrow, to short and the chin hung out the bottom.
The second pic is my brother in his Mereel Version 2 armor. The helmet is my old Don Post 95. The helmet is now sized corectly to his body and armor. The problem with the kit at the moment is not that the helmet is too big, it's that the shoulders are too small. A much cheaper and easier fix than a new helmet.
The third pic is my brother in his MEreel kit with his SDCC upgrades. The helmet is the same Don Post 95 helmet. However, the upgrade done to balance the helmet was to dd new, wider shoulders to the kit that foucs the eye downa nd out rather than up and in.
This should be a template to use when you select the helmet for your armor and body and for when you design your armor. Regardless of your body type and size, you can find a helmet that fits you. Although I am adamantly against the Rubies 1 piece helmets, if they will fit your frame, they are the proper helmet to select. At no point have we at the MErcs or will we, unless you're build a screen accurate Fett, tell you that you have to buy a $300.00 Bobamaker helmet or a $400.00 BKBT helmet. But, we will tell you to buy the helmet that fits you best. In general, unless you are VERY small, a 1 piece Rubies or Jango will NOT work for you. In general, medium/large to large framed men NEED a 1:1 movie sized helmet. Medium framed men need something sized to the Don Post 95 or the Asok LFL Jango helmet. A smaller framed man can wear a Rubies 2 piece Jango. For woemn, most women can wear a 2 piece Jango or a Don Post 95. GEnerally a movie sized helmet will be too big. The 1 piece Rubies should really be saved for children unless you're so small that you're the exception to the rule.