trench digger,

Statistically speaking you really need several hundred "trials" before you can be confident that the results are significant. Of course if the system you are looking at only gives you one bet a week then this is not practical. With the results you quote I would say you could start betting now but start with a small bank that you would not be too upset losing - say $100 or so and with a 90% strike rate you could bet 10% of that each time (so first bet would be $10). If your success continues then you should be able to build you bank up over time.