Looking to make a Rimowa carry on purchase and have narrowed down my choices between the standard Cabin 9 gal Aluminum vs the Cabin PLUS 11.9 gal Aluminum carry on.

I've seen people with the Cabin Plus but wonder if these bags really fit overhead on US domestic flights (the measurements are well beyond the standard allowance...but we know how some can slip by). The extra space this bag has is very ideal for me...though the overall size is of concern.

On the other hand, the 9 gal probably wouldn't cause me any issues boarding a flight, but it is slightly smaller than the Cabin Plus. Does any one own either bag and can speak on their experience? I currently use the Away Carry On (not the bigger carry on).