I have a suspicious blue temp sensor on my 2.1 DJ. I rang Dick Turpins (VW Crewe) for a price ->£36+

Just checked the usual 'local' webshops and they are about £6/7. Now I'm always a bit nervous about sensors and their quality.
Can the cheaper units be reliable or do I invest in genuine, is this a case of 'you get what you pay for'???
Cheerz