[NTG-context] dejavu: inline math fraction spacing too tight?

Hello, Using the dejavu font, inline math fractions (e.g. $a/b$) look to me to be spaced too tightly. Below are some minimal examples: \setupbodyfont [dejavu,12pt] \starttext $a/b$ $1/2$ $π/3$ \stoptext Is this indeed the desired spacing? What do others think? Thanks. Alan