http://www.ebay.com/usr/artinvest389
I did test random samples from the data against other data providers and I am using it every day an yet to find errors or mistakes...
Sounds like fun for those that like technical analysis.
Use your imagination, with data like this you can test value investing, arbitrage, trend following...
For any type of investing test you'll need to know the price of the security on any given date in the last 20 years...
Your comment is very perplexing in content and tone.
That said, I think I might not have conveyed my original question well enough - what I actually meant was 1) is the data accurate? (you sort of answered this by saying you compare it to presumably licensed sources) and 2) what actually led you to searching for financial data on ebay? (you didn't answer this, other than "it's cheap").
I'm basically wondering how you did the mental calculus that concluded ebay was a good place to check before you verified the data was alright.
If it was not, I would have notify the seller, eBay and PayPal and get my money back...
Before this data, I was using Quntopian, but the huge limitation there is that you cannot test on the whole market, you cannot download their data, etc...
Anyway, I am trying to give an honest advice here and to prevent people of losing money because they don't know what they are doing...
Do you have personal experience buying data from ebay? Why would you do that?