I've been researching these lights and it appears that the UI is the biggest difference.
Someone with Olight experience can correct me if I'm wrong, but the T25 has 5 brightness levels activated by turning the head along with strobe/SOS modes activated by pressing the power button.
The T25-T (Tactical) version has 3 brightness levels and strobe/SOS modes all activated by turning the head.
You can select the two versions in the comparison list below to see the difference:
Thanks e-dogg, Its suprising olight made 2 lights as similar as that tho but I can't be doing with the "twist to change levels " stuff.
You saved me from buying yet another I won't use.
Geoff
The T25-T seemed to be slightly more efficient than the regular T25 at least originally. The T25-T also has a forward clicky which I prefer. Compared to most XR-E lights the beam is perfect with no dark rings at all, or at least mine is.
TBH though my 2 year old L2D (smooth reflector) throws just as well as my T25-T and although it is not "tacticool" it still has excellent runtime. I would pass on the regular T25 personally and go for an L2D if you can find one, unless you want a perfect beam pattern. I find the twist to change levels can get slightly annoying over time but all in all its still a good light.