Fly Formula helmet/goggle fit question?

I don't think you'll have to worry about fitment in the Formula. Fits my Prospects just fine.

I use 100% Armega and Accuri goggles. Both fit great.

I got a large cc and it was too small for me I’ve worn a lot of brands only one I had an issue with

As a counterpoint I just bought a large cp and it fits almost the same as my last helmet which was a large moto9. Felt small at first but the liner packed out quickly and its like a glove now. Large Arai was the only helmet that has been too small for me so far, still wore it for years lol. Couldnt close my mouth because my cheeks were getting squished in between my teeth.

My 100% fit just fine even with the nose piece 

Fair play maybe a different head shape I’ve been running an arai

best to try a new brand or ok if they do returns 

I wear a medium Formula CC with 100% Racecraft/Strata goggles. All is very good, but those are also smaller frame goggles by today's standards.

It looks like the Rockstar Husky riders run the (large?) premium Scott goggles with no problems.

While I really like my Fly Carbon, I do struggle with larger framed goggles.  They end up contacting the outer edges of the helmet and that results in the goggles being pushed down on my nose.  I have a couple pair of basic non-outrigger EKS goggles, and they fit fantastic.  My Airbrakes get pushed down a little bit, and my FlowVision goggles are even further down my nose.  The youth version of the FlowVision goggles don't have the outrigger and fit just fine.

The 100% armega and Racecraft 2 work good for me with the formula helmet. Fly actually has some cheap goggles that work pretty good too but they are a tad smaller framed.

Second this prospects fit fine in fly helmet 

I personally like the fit of bigger goggles in the Formula. It has a tall area for goggles and if you use small/old school goggles and face a lot of roost, the half-inch gap between the top of the goggle and the brow of the helmet is a spot for sand to rain into your goggles. 

I use Flow Vision and they work well to limit this gap. 

Just wish the visor was a little longer/wider to provide more roost deflection. I run an old lense on the front. 

Airbrakes and Prospects fit good in mine.

I will say the combo of the formula air flow plus the prospect air flow makes my eyes water more than the oakleys do. 
 

Prospects don’t make my eyes water in my Bell. Weird.