Koni without a doubt. The Bilsteins seem to have a good rep, but when you get into Koni price range you might as well go for those.
As for the rear ARB, I got mine second hand, it was perfectly serviceable. It was about 60% of the new price, including delivery. Just keep an eye out on Ebay, they pop up occasionally. Don't forget to look in the VW section as well, they're interchangeable and there's a lot more Golf's out there.