Definitley try a different wax as the Megs doesn't have very good durability, many choices out there I use
www.cleanyourcar.co.uk for most of my detailing stuff
most of the megs stuff is expensive weak and nasty crap in a glammed up bottle.
No Sweeping generalisations here!
Nothing wrong with Megs stuff. Have you tried any of their professional or bodyshop range or just the stuff in Halfords?