M42 rebuild - genuine/non-genuine parts

[cheesebox]

Having been quoted £500 to replace the profile gasket on my318is (the one which requires the head to be removed), I'm starting to think about doing the job myself. Whilst I'm at it I'll probably replace the timing chain, guides and sprockets. Assuming I don't bottle it first!

I've got quite a list of parts required, but not priced it yet. I wondered how much I could replace with non-genuine parts, eg from eurocarparts, but am concenered about these parts wearing out or failing sooner than if I used genuine BMW parts.

I'd have thought some non-gen parts like cylinder head bolts would be fine as they don't tend to fail or wear, but what about things like gaskets and timing chain/guides? Has anyone had good/bad experience of anything similar?

[Brianmoooore]

BMW don't make these parts for themselves, and in theory you should be able to source identical parts in a different box from ECP or GSF.
Don't assume that ECP or GSF are always going to be cheaper than the dealer on everything.

[tim_s]

I've just rebuilt my m42, so have a fair bit of experience of this. Used a victor reinz HG from GSF, i've used this brand in the past with lots of success. head bolts likewise from GSF, febi bilstein. profile gasket etc came from BMW.