Is there a compelling reason to change the switch? The rocker-type activation on the TLR 1-4 series lights is by far the best light mounted switch on the market, IMO. It is very positive, easy to manipulate with the firing or support hand, and the TLR-1, in particular, is an extremely robust light. The switches on the Surefire are second and the APL is a distant third.
FYI - for sure confirmed it runs a CR123 - https://www.streamlight.com/en/produ...il/index/tlr-7 - Which is at least good news, switching to a CR2 would be silly.