[NTG-context] lower superscripts in MkIV -- too low?

Dear math typesetting aficianados, In the following example, \starttext $x^3\ x\mathstrut^3$ \stoptext the superscript without the strut is about 2pt lower than with the strut, using MkIV. With MkII or plain TeX, they are the same height (at the higher position obtained by using the \mathstrut in MkIV). My eye tells me that the higher position looks more right. Do others agree? Or, if it's a matter of taste, is the difference configurable so that one can get the MkII behavior even without the \mathstrut? -- -Sanjoy