I have the Fenix HL60 and the first version of the HP25. Reasons were the rechargeable access, super bright for tracking, multiple power levels. I believe I read somewhere they flash when battery gets low. Mine has not, but the power level you are at, will automatically drop to the next lower setting when battery level is getting low. All of my electronics are rechargeable so I never have to carry extra batteries, just a single power bank. It was a perfect system as my phone utilized the same micro USB. But now my new phone uses a C port. So I will be forced to carrying 2 cords.
I have been running the Fenix for years and see no reason to switch- rock solid. My HP25 has close to 100 hrs on it, and water proof proven. It is heavier with the battery pack in the head band, but I still prefer that over the battery pack remotely worn like the newer versions.
I cut up a bull at night and never knew it was there, hiked out in the rain and it was going strong all the way to the trail head.