I carry a Stinger XT, tail cap model. Nice light, rechargeable and bright. Used to carry an original stinger, I liked it better, just not a huge fan of the tail cap switch. Also have a rechargeable Mag light available if I need it.
My new dept does not allow weapon mounted lights... but I carried a M3 w. my last and loved it. But different strikes for different folks!
Stay safe
John