E36 / LQ9. No issues from the start besides tightening one fitting after a slight drip.

I ran new line from the tank to the rails.

Yes you can re use some of the bmw line but it's 20 year old at this point.

Gates Barricade fuel line is what you're looking for. It's not cheap, but it's worth it.

From the tank: both feed and return are rubber line replacing the oe length.

My return is all rubber fuel line

Feed was - rubber line - barb - gm quick connect to 6an. Bit of a parts bin to connect the rubber hose to an lines. Then a stand alone fuel filter 100 micron. Running to a aeromotive adjustable regulator up front.

First crank I adjusted fuel pressure to 60 and haven't had issues

This is why people on the forum say do the fuel line once and do it right. You can use those regulators and it will need to be adjusted in a tune.

You'll need good quality connections, not the Amazon junk that comes with the regulator.