I know eggzactally where you're coming from, every time I change oil it always ends up everywhere no matter how careful I am. I think the last time it was ok right up until the point where I put it in a can for disposal - there was this *gloop* as it was going in and there it was everywhere again

The BX 16 valves were the worst, the engine had some weird way of building up an air lock as you filed it, no matter how slowly it went in suddenly it's just gop a whole load of (clean, admittedly) oil all over the top of the engine. Then there's messing with sump drain plugs, which are always somewhere you can't get enough leverage without jacking the car up 12 feet in the air, and oil filters that weld themselves in place so you need to get the chain wrench out to somewhere inaccessible and then they gloop oil out as you're trying to move them... These days I have a garage with mate's rates
Oh yeah, and just because you've been going there for 12 years doesn't mean they don't see you as anything more than another mug. Look how insurers treat return customers
