Hi I mostly agree with the analysis done by Doomsmoker, but I think there is one point missing which I think is crucial; Pip expectancy of the system. This is because systems with low pip expectancy (say below 3), are not profitable in AT. If you subtract the markup of AT plus some slippage you get a 0 pip expectancy for these systems, which basically tell us that there is no money to be made on the long term.
This criteria further excludes system such as Steady profit, FXBSR and Vine.
The other point I have been noticing is strong correlations between the scalpers (Ninja, Night profitICMarkets and GBP combo), so I would be cautious on following all at once since when a loss comes this can be very large due to this correlation. Moreover all this sytem trade the GBP quite heavily, with GBP combo being 100% dependent on one currency.
Regarding brokers we should share as much data as possible to be able to conclude anything. I have data for IC markets, Axitrader and Intertrader, but there are many more brokers available for AT. Does anyone have data for other brokers different from these?