Wow, I just spent some time scrolling all the way through this thread from start to finish and, having been a Titan Plus owner for only two years, I'm happy that Surefire has solved any of the light's early flaws, real or perceived. Mine is just fine as received and spends its life as a keychain light; I buy Surefire because they can and do survive such a tough life and still turn on every time.
I do have a question though. Early on here, someone asked if a lithium AAA battery could safely be used in the light without harming the emitter. I didn't see that was ever addressed and now I'm wondering about it. I have no issue with the Eneloop Pro battery the light comes with, but living in a cold climate have considered substituting a lithium. Is emitter damage possible if I do so?
Mine is always in my pocket since 2016 and it gets used multiple times every single day. I do use Lithium AAA primary batteries from time to time. No noticeable harm so far.
My go to batteries are Standard (white) Eneloops because they are more durable than their Pro (black) counterparts. The Pro's offer longer runtime at high mode when new but they degrade sooner, despite my efforts to maintain them properly. They eventually fail to provide the current that is needed for high mode, even when fully charged.
Properly maintained Standard Eneloops, on the other hand, do enable me to use the high mode, albeit for shorter periods. I mean; step-down to medium happens quicker but they keep enabling me to use the high mode after many, many charge re-charge cycles.
I use Lithium primaries when my Eneloops are in the charger for long periods (cycling or break-in), as well as backup batteries when travelling (for not carrying along a charger). I feel safe when using them and I did not regret so far but frankly, I don't know if they put extra strain on the emitter.
Needless to say, alkalines are no-no. They never get their way into my good old, trusty Titan Plus.