It's 2020 as we speak and how many of you are still using this little light?
I recall being a little crazy in procuring these back in the late 2000s when modding options were open to me -- particularly with a custom-made heatsink design which allowed me to have a handful of customer modules made (based on Sandwich Shoppe drivers). And as we speak, I still have one of such example used as EDC (in my daypack that is), with an NG1000 driving an XPG2 (S5).
As for tailcap boot, it's flimsy and will break after prolonged use. Luckily theunmodified KD 14x8mm ("soft press") serves as a good replacement.