About the Big Finish audio drama, they continue the Classic Who in the main range, so if you haven't watched the show than it can be hard to follow, but I think people should watch the 8th doctor movie with Paul Mcgan and than listen to the new 8th doctor series with Paul Mcgan and Sheridan Smith, the synergy between the two of them are near divine, and dare you to sit still after listening to the end of the final chapter. The audio series take the best of the series, remove almost all of the nonsense of the TV, the quality of writing is really consistent. (none of the nonsense shipper war in the new series, character development is really belivable).
In short, Whovians should listen to Big Finish, especially those who watched the Classic. It can be hard to get into but when you hook up you don't even want to watch TV series.