The fact that bleeding them is an absolute nightmare, the fact that if they have so much as stepped over the overheat threshold for more than a few seconds, they warp, the fact that most independants haven't got a clue about the cooling system in general, and treat it like any other car.Whats very skilled about it fox?
If it lasts five minutes it hasn't been repaired has it?
I had my cooling system fail 5 times during my e36 ownership (same cooling system).
.
You try sourcing a complete second hand engine for £100, you wont. Camshaft/Crankshaft position sensors are utterly pointless used and are not cheap from a motor factors and can be a bloody pain to fit, etc etc.