do I have a real significant edge?

[WhiteKnight]

no reason really.  i'm sure it doesnt make much difference anyway

[Spiff]

47% is always a huge edge, but the spin sample is too small.   I would say at least 100. 000 placed bets or more.   Try to get someone to program it for you.   Handtesting will kill you and is really disapointing when you reach 47. 000 spins and it goes into red figures.

I so much subscribe the last sentence mate! 
In my experience it's sadly true, even some thousands spins could not be enough, though with flat betting things are a bit different --> fb systems do not collapse all in a sudden, but you can sadly realise after lots of spins it all ends up in a big draw

[Spiff]

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