Having got a measly 500 miles out of the SRAM PG 950 chain that came fitted to one of my bikes I had a look around the web for something longer lasting and came across this article: http://www.cantitoeroad.com/chains
The test is conducted by Wipperman the manufacturer of Connex chains, but provided they haven't outright lied it looks to be a fair test. However, one thing the tests don't cover is the price, so I decided to find out and using Google shopping to find the best prices for the chains here's what I came up with:
I have been using Campagnolo Record 9 speed chains ever since I first came across this article a couple of years ago and they easily outlast the SRAM and Shimano chains I've used in the past. Two of them I have, have done well over the paultry 500 miles I got out of the SRAM chain and according to my chain wear checker tool are nowhere near 0.75% wear yet.