Hi, I have done about 25,000 km on Bio, mainly on b20, but a few tousand km on b40. With B20 I get identical mileage to d100, on B40 I saw a 1% drop in mileage. No noticable power change between the 3, but the motor runs noticably smoother on bio than dino. A lot less smoke on bio too (on my bagged out 1.6td anyway)
No leaks so far, but it hasnt been a year yet.
The station I buy at recently put a BIG warning on pump about gelling, they recommend B40 for above 0 degrees celius and B20 for above -10 degrees celsius.
Free fuel??!!! Dang where do I sign up?