Karnataka has 3 pairs of sampark kranti- highest for any state in India and also runs 9 days a week ( 5 days +2 +2 days CDG SK) which also is the highest. But these SKs serve other state, the 12629 and 22685 serve PUNE mainly and have slow speed and 12649 serves SC and SBC. So the name is in my opinion actually a misnomer, and more KSKs cannot be started and a new SF can be started to serve other parts of the state. Anyways SK have normal SF priority and few stops, so a normal or even ACSF will be a good option with no flexi fare.