I have used SwiftKey for a long long time on 3 different phones including any SwiftKey betas. Same with Swype.
I also have tried almost every other keyboard available alpha, beta, free and some paid.
SwiftKey has always been my default and now as version 4, I have updated my GS3,my Nexus 7 tablet version, wife's Incredible 2,and my old Incredible 2 I upgraded from via wifi that has no data. I also paid for extra one because I have multiple users on N7 which has separate profiles for wife and me.
The only thing I have not done is sync it with Facebook, Gmail of SMS. The results still are incredible.
Sent from my VZW Samsung Galaxy S 3.