Tlr1-hl-x is a huge upgrade over the tlr1-hl and should be purchased - Streamlight TLR-1 HL-X USB Multi-Fuel High Lumen Rail-Mounted Tactical Light

TLR1-HL-X can be sold in two configurations; with SL-B9 batteries OR with CR123A batteries. The SL-B9 battery has a USB-C port to recharge the battery while the CR123A is a one time use. I would heavily opt towards the SL-B9 batteries as you will be able to use them time and time again with recharging.

I swapped out my TLR1-HL for the latest, TLR1-HL-X. I loved the brightness of the TLR1-HL, but was not a big fan of the operation. If you were a right hand shooter, you had to use the support hand to keep the light engaged while shooting
(in temp mode). Other clunky ways of using the TLR1-HL included flipping up the switch with the support hand thumb (not easy) or tilting the handgun into your support hand to engage to always on. In running multiple low light shooting drills with the TLR1-HL, this was not optimal. Where the TLR1-HL lags, the TLR-1 HL-X makes up. With super simple support hand thumb (right handed shooter) the TLR-1 HL-X light is engaged and stays on. This allows for quick maneuverability of turning on the TLR-1 HL-X light and actually using your support hand for a full grip. This is a massive upgrade over the TLR1-HL which shooters would use the support thumb to keep the light on, but suffer proper grip with the support hand.

The light of the TLR1-HL-X is noticeably brighter then the TLR1-HL. I used rechargeable CR123A batteries in the TLR1-HL and with the same rechargeable CR123A batteries found the TLR1-HL-X eats up the life of the rechargeable CR123A faster then the TLR1-HL. It is a small price to pay and considering you can frond load the batteries without taking the light system off.

Holster Fit
Once the TLR1-HL-X was installed, it would not fit in the same holster made for a TLR1-HL. My sidearm would stop a bit short of fitting all the way into the holster. However I have an adjustable holster which allows for small adjustments in width. I was able to change the spacers in the holster and once I did, the TLR1-HL-X fit like a glove. If you do not have an adjustable holster, you will probably will have a challenge in using it with the TLR1-HL-X that is designed to fit the TLR1-HL.