INFI is superior to SR-77 in 3 regards:
1) wear resistance - it holds an edge better when cutting soft things (like food, textiles and so).
2) corrosion resistance (it comes close to some stainless steels category in this regards).
3) deformation resistance (and compresive strength) - it's more deformation resistant than SR-77 (something which is usually forgotten to say, but in Noss tests from knifetests.com you can see this very clear in the behavior of the tip and edge of the Scrapper6 and the Skinny ASH-1; the two knives have pretty similar sizes).

In lateral strength (which means bending for good or breaking a steel bar by applying lateral pressure) the two steels seem similar. And they are the same in impact resistance (chip and break resistance).

I won't comment on the price ratio between the two, because the price should normally reflect the production costs more than the utility value of a product.