I've been looking in to these myself for some DIY diagnostics on my vehicles. Seems that the overwhelming majority of the ELM327 products typically found on Ebay and Amazon are cheap clones from China. Always seem to see varying reviews from them, either it works excellent or junk. Apparently the v1.0 code lacked copy protection and thats why so many are pirated copies. It's likely that any cheap copy will run the v1.0 and not the latest code version 2.0. There is no v1.5 that most advertise btw, progression was 1.0 > 1.3a > 1.4b > 2.0. The Elm chips are list price of 14.50+ so I think it's apparent those priced below that are likely not legitimate.
I'm not sure if there are many properly licensed "cheap" scanners being produced but you can check out Scantool.net. Their support is only available via forums, but that is more than you would get from the alternates it seems. They also have a multitude of specialty software suites for access to proprietary vehicle protocols. It can get expensive pretty fast depending on what you are looking for, but seems to be vastly more professional than the other options.
Only other thing to make note of would be the wifi models tend to be more expensive but are necessary to work with apple products while android can use the cheaper bluetooth alternatives. You should be able to use a laptop with the bluetooth version as long as you have it either built in or use an adaptor.
Depending on how much you were looking to spend this option may be more than what you were looking for, but should allow greater flexibility and support for future firmware upgrades.
