Strategies testing. Datafeeds differ a lot

[michel rood <michelrood@xxxxxx>]

I'm testing some commercially available strategies. Unfortunately, depending on datafeeds I never get the same results. Results differ from feed to feed a lot !!! E.g. TS-6 strategy results differ a lot from Tenfore, by many people stated the best feed, and then I mean a lot. Even testing with data from the same provider, tenfore, and sent to me by different users, even then I get not the same results. Some users should go into the market and others don't or the time is totally different, hours of difference.
I assume many of you, with testing strategies, have encountered the same problems, let alone system trading brokers. How did you solve that, if possible. If you use two datafeeds, do you get the same results with a strategy, e.g. tenfore and esignal. 

Thanks in advance.