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So everyone I know uses AFR over LAMBDA I don't know if it's a USA thing or what but my primary question: is can I achieve the same results with LAMBDA as AFR or does one have an edge over the other?

Yes and no, technically, different fuel blends - 100% petrol (gasoline) Vs a blend Vs 100% ethanol Vs 100% methanol all have different AFRs but similar lambdas, as that is the amount of oxygen left in the exhaust gas.

AFAIK, all AFR meters work from the lambda and convert it to what it AFR it represents with a 100% petrol (gasoline) fuel. This means that if a pure ethanol fuel is used it will display, say, 12.5:1 when it is actually 8.5:1 (can't recall the exact figures off hand) but if using the lambda a direct reading can be done that takes the AFR variations out of the equation.

If you're only going to be using a pure petrol/gasoline fuel, then AFR should be fine, but if you're ever going to use a different fuel then getting familiar with lambda will be a definite advantage and the business seems to be going that way.