There is a difference in weight.
People who've put the V-6 springs on their Zetecs end up with the front slightly jacked up.
I'd assume that your front end would ride a bit low with the Zetec springs. Might look cool, but I'd be afraid (for me) that they'd be too soft. Kind of like when people heat their springs and squish them to lower their cars. The car rides "tight, yo" but without the increased rate, they go around hitting the bumpstops all the time.
I don't know how severe it would be, but if you don't have money/time to experiment, I'd steer clear. If you do, then it might be worth a shot.
