Best Double Action Revolvers

Double-Action triggers in a wheel gun offer a lot of advantages, especially when considering user safety; the long trigger pull helps to prevent negligent discharges.  We tried making a list of the best double-action-only revolvers, but there were only 3 or 4 that were worth showing, so we re-made the list to include revolvers that could be fired from either single- or double-action.  Which ones would you consider buying?