Hmmmm. Who knows? I'm being somewhat fecetious, but my point is that "Plus X" is a vague and relative term, at least to me.
I agree that 17's are probably the opimum size, all things considered.
Function before fashion.
'96 Contour SE
"Toss the Contour into a corner, and it's as easy to catch as a softball thrown by a preschooler." -Edmunds, 1998