The market data I am using is Bitstamp data from Bitcoincharts.com. I get the data by looking at a daily chart for "all time" and clicking "load raw data" at the bottom of the chart. There are 5 or so days which need to be cleaned up (price = infinity, etc.). I set the market price on these days equal to the price from the prior day. It's imperfect, but it gives the general idea.
I performed the same simulation based on the 1.
http://bitcoinchain.com/export, 2. bitcoincharts.com csv and in the both cases I have the slightly different results than yours - no crossover yet - and in both cases the results match one to another.
If you're getting
slightly different results backtesting, then I wouldn't be worried. If I started backtesting a day earlier or later, my results could have potentially varied by several hundred percentage points.
In terms of what triggers me to actually enter/exit the market, I use a chart on ZeroBlock trading platform, so I don't use the BitcoinCharts feed.