The market will travel up and down on all these cars. Cobras have a limited audience and like it or not are recreations of the original which have a specific number available. Replicas are merely worth the sum of their total parts. In other words cost of building, some get more from their ability to entice i.e. Webers, era correctness, or creature comforts like top and side curtains. If manufacturers continue to flood the market in conjunction with streamlining their abilities prices will continue to drop.
Look at CSX glass car rollers for example 50k, once a factory is set up building it becomes easier to accommodate price adjustments. It will be like anything else the cream will flow to the top and the rest will belly up. CSX, KMS, ERA, Unique, and SPF should have staying power as they have built brand recognized type replicas. The rest will need to prove themselves or face difficult situations.
Auctions like BJ without reserves will either provide some great deals or they will scare away sellers of Cobras as prices are soft. I would never consider selling at an auction w/o reserve, too many variables in that sale for me. With BJ last outing selling CSX glass cars at 65-70k hard to compete. Buy them to enjoy and use caution as an investment.
Here is an older ERA for 37,500 with FE: Tough to beat that!
http://cgi.ebay.com/ebaymotors/1966-...em230236945770