Its over kill mate I ran a G60 things got hot, so using a lower temp switch made sense, but just for you knowledge the ones you can use fit a TDI transporter, don't remember the part number, but using VAG they can cross reference the part which is what I did at my local VAG place. You are better off getting decent anti freeze and distilled water in the rad. Even use Holts two part flush before sticking in the new temp switch.
Downside the fan kicks in earlier and longer which means if your fan is old it can shorten its life span just making you aware