got some of these ready to be fitted as rear originals are t.b.h CRAP!
have a sub/amp ready for the boot but not sure if want to upgrade head unit yet as current one doesnt have pre outs and an old dvd unit i have has but ...old!! and unbranded..suprisingly fronts are ok but may sound crap when the vibes are kicking!!
anyone recommend vibe? would a better head unit better utilise these upgraded speakers?

Upgrade the headunit, it makes a huge difference to the sound quality.

A better headunit will make all the speakers sound better, more so when you bin the standard kit.