most accurate loudspeakers....

It depends on what you mean by "accurate."

A good place to start is to check out what most of the prestigious studios and mastering engineers like to use. Full range accuracy at both low level and realistic live sound levels is actually quite rare in home hi-fi.

Viridian- I do like your thinking. If my man isn't to remote, he should go to dealers in his area toward the end of the week and see if they won't let him take home and audtion over the weekend. The latest Merlin monitors are getting a lot of press about their "accuracy". Their acoustic suspension designs as opposed to ported so their bass may be tauter and with better timbre than the latter designs but with less abundance. The word accuracy makes me think of Dynaudio, as well (Contour series and up). Chances are, my man may not know what's gonna groove him the most. In home auditions are the way to go.

the phrase "more accurate" is an oxymoron. all speakers are inaccurate. accuracy is dichotomous. there is a state of accuracy and a state of inaccuracy.

one can use the phrase less inaccurate to indicate a state which is closer to accurate, i.e., perfection.

as has already been said it is difficult to quantify inaccuracy. it is possibly to provide measurements of various parameters. then what ? how do you quantify accuracy, given measurement statistics ?

why not consider which speakers are most resolving, if that is your goal ?