Its funny all this hype from ponzi scheme arbitrage advertisers. I have the hard data of millisecond by millisecond arbitrage opportunities from 6 major exchanges on which my bots operate.
Simply anyone who says they do profitable arb by hand is a liar, or cannot count for exchange default risk or payment service provider risks. No human can compete with my bots acting within 20 milliseconds by searching for thousands of arbitrage routes using 10 different IP addresses to gather the fastest data that beats public services like Bitcoinwisdom by seconds.
All I can say is that after bank transaction costs and currency exchange costs last month used to be 1.5% daily risk adjusted return on the whole capital, but this month so far is pretty shit 0.5%. So guys who claim 1%+ per day for this month by hand are pathetic liars.