Clinic ace, roundup, or anything similar will kill EVERYTHING it comes into contact with. So overspray can be a major issue. That type is called a pandemic killer.

Grazon Pro (previously called Grazon 90) is a systemic killer that will kill sophisticated plants, but not grass

Grazon shows very rapid effect - in the right weather conditions, a couple of hours. Clinic ace takes up to 2 weeks to show effect, so a lot of people assume it isn't working, as they don't see rapid effects.

Thanks. I'm not to bothered about other vegetation dieing off as I plan to dig up the garden as the last owner has let I over grow and I want to start with a blank canva's. Plus I will be laying artificial turf once I've levelled the ground.

In which case, Clinic Ace (or equivalent) is what you want applied. You may need to get a professional in to do it, as it is restricted purchase. I had to produce my CPH number for the smallholding for the last purchase, and in future I will have to produce my spraying certificate too. Vicious stuff.