Cheap chain vs expensive chain
 

What's the difference?

the cost?

you don't say what specific chains you wish to compare but as a generalisation , current top of the line chain designs (vs a basic economical chain) will usually provide for improved speed , consistancy/reliabilty & accuracy of shifts, & at a lower weight.
most modern chains are designed and optimised to suit a specific manufacturers drivetrain configurations to maximise performance

Depends on what you are using it on and the chain itself, some of the most expensive chains I have ever used were also the shortest lived. They were designed to be extremely lightweight, and as a compromise wore very quickly.

I have a couple of $5 1/8" chains on IGH bikes that have seen over 10,000 miles of service. I have noticed that the OEM chain on my 1972 Raleigh Superbe is about 1/3 heavier than the current replacement chains I have been buying.

Aaron:)

I have had very good luck with SRAM PC-58 chains.

Well I wasn't thinking about a specific bike but it sounds like compatability is the real issue, and wieght versus durability versus cost (within a given brand) is my prerogative?
So I should put a Shimano chain on my shimano bike, a sturmey archer chain on my SA bike and a rusty old chain on my rusty old schwinn?
I found another thread where a couple of guys said that SRAM works pretty good on a variety of gears for a decent price. Would it be a bad idea to try to find one decent brand that works on all my old bikes?
Thanks for the clarification, I haven't been able to find much on this.
ben

My favorite is the Wippermann Connex 808. It's nickel plated, so it looks good and resists corrosion. The Connex link doesn't frustrate me like the other brands do. I used to get them for under $20, but they're German and the price has gone up as the dollar has fallen.

I've been using the $12 KMC Z-Chain 6/7 speed. Usually works reasonably well.

I've had the whole price range. The more expensive ones seem to shift a little better. But then that one came on my Spcialized with the XTR RD so that may have had something to do with it....

Other than that just the amount of shine. And you KNOW we all are uncurable victims of Shiney Object Syndrome (SOS for short).