So towards the end of last year I purchased a complete timing belt/water pump kit for $280. I got everything I needed, including coolant, I was set! Had the stuff professionally installed, finally had peace of mind over my timing belt.
Recently, about 8 months and 18,000 miles later I start getting an intermittent obnoxious rattle from under the timing cover that only occured between ~1000 and 2000 RPM. After doing research, I realized the kit I bought has had numerous cases of the tensioner (specifically, the tension dampener - what actually creates the tension on the belt) wearing prematurely and making the horrible rattling noise I was hearing.
The reason is the tensioner parts are not made by the same people as the OEM VW/Audi ones - they are made by NTN in Japan. OEM ones are German made.
I started taking the car apart and sure enough I could push the tension roller around with minimal force - the tension dampener was obviously bad. This is the part I'm talking about:
So I started the process of removing the tension dampener. Meanwhile I called up the place I bought the kit from. Although it had been almost a year since I bought it, the customer service rep immediately offered to ship a new tension dampener to me.
So now I have a new one on the way.
My main point is it's not just one kit that carries the NTN tensioner parts...MANY places sell the same Japanes NTN parts as part of timing belt kits. Dieselgeek, ECS Tuning, basically any timing belt kit that costs ~$250 will consist of Japanese NTN tensioner parts and not the OEM German parts.
The OEM parts literally costs almost twice as much. ECS now sells a completely OEM kit and guess what, it's $550:
ECS Genuine Ultimate Timing Belt Kit
Their cheaper kit uses NTN parts as stated in the description:
ECS Ultimate Timing Belt Kit
Notice Dieselgeek's kit uses the same NTN parts as well:
Dieselgeek Timing Belt Kit
That said, not all these tensioners go bad so fast, obviously. A lot of people have had no issues with the NTN parts, however it might be a good idea to fork out the $130 for the genuine VW/Audi tensioning dampener if you're not comfortable with possibly having to replace the tensioner yourself or pay to have it replaced early. My OEM tensioner lasted 92,000 miles.
So choose what you buy carefully.