Well, my indy refuses to use aftermarket hoses ever since he had to buy one of his customers a replacement engine. That's enough for me to use nothing but OEM replacements for this service. As I recall they were less than $500, cheaper than a single (dealer only) AC hose I had to buy for the 240D a few years ago. Personally, it's not worth my time to have them fabricated if I can get them from the dealer with a phone call.

I agree they need to be replaced at some interval. I replaced the original hoses when I bought the 300D in 2001, and replaced the hoses and the oil cooler (both OEM) when I replaced the engine about a year ago. It's still cheap insurance.