I posted that link because it looks like they did a pretty detailed job a testing the three intercoolers. I'm not trying to sell anyone on the ECS one. Regarding the ARM...I'm willing to bet that you'll have to trim the inside of your Golf bumper the same way my friend had to trim his to get the NS IS38 one to fit.. They all pretty much install the same way. The GTI has a bunch of room behind the front bumper...the Golf may not have the same amount of clearance.