Agreed. The Eibach ARB kit is one of the best mods you can do to a MK5, irrespective of what suspension is fitted.
A lot of folk fit a rear bar only, but you only get 50% of the potential. Most peeps think a fat front bar = more understeer, but that's actually false. It's all about pivot points and moments of inertia, and other boring science stuff. In other words, imagine a dining room table, with a chap at each end trying to twist it, opposing each other's forces. Obviously the 4 legs of the table translates to your 4 road wheels. You want two equally strong men keeping the table flat on the floor, rather than one mahoosive hulk at one end, and a skinny latte soy boy at the other.
In other other words.....don't stiffen just one bar, do both.