Just had some work done and normally use TPS for genuine VAG parts but was told by one of the staff to go to eurocarparts for my clutch as exactly same part was much cheaper as they couldnt compete on price . TPS £600 for clutch and flywheel kit and needed clutch returned to get a £50 refund ,Euro £350 for exactly same sachs clutch and flywheel kit. i now need a front o/s wheel bearing kit do i pay £120 for TPS skoda part or £87.60 for best example euro have of the part made by FAG/Snr I dont mind paying a bit extra for definite better parts but i feel many items are made in same factory just labelled diferently . I bought two drop links one a Lemforder for £15 from euro and a TPS part stamped VW they both look identical .

FAG is I am sure an  O.E supplier and part of the LUK and INA Group so top quality

Have you looked on gsf too they have 45% off today with the code wed45. I could get a clutch kit from there for £130.

Personally I've never thought of oem being any better than parts from gsf, euro etc

euro car parts do a whole range of the same part , you can buy the same part for £8 or you can pay £12 or £20 supposedly going up in quality - dont think i would like to use any other clutch than a Sachs or LUK  to save £20 - £30 < Its hard to imagine though how one brake disc could be more than double the price of another make ,can there be such a marked improvement in a steel disc ?

I needed to do a rear bearing on mine last year (reluctor ring was failing and bringing up warning lights on the dash) got a FAG rear bearing from Euro Car Parts and when I took the old (original) one off, it was a FAG bearing too. 

I'll try to stick genuine OEM parts as best I can, especially for service items.

lots of parts claim to be oem or equivalent - i have used euro for a few years now and not had a problem with any parts but i do tend to buy the dearer end of the possible parts suitable - lemforder tends to be the option often.