Rockshox have a reputation of being dependable regardless of price range, something which certainly can't be said for SR.

But switching to a longer travel fork will change the steering response and the handling of the bike. Functionally, it's (usually) a non-issue, the bike will still remain rideable.
But you might or might not like the feel of the bike, and it will increase the strain on the headtube/downtube joint.