I'm going to upgrade my SF G2 P60 lamp assembly to this http://www.dealextreme.com/details.dx/sku.11836 My question is can the stock SF G2 lens which is plastic can handle the heat from the new R2 drop in? Thanks.
The question of whether a LED drop-in will be OK for the G2 is raised quite frequently.
Surefire do not recommend it, and they make a different head for their LED version of the G2.
The answer is probably best summarized as "If it is a high-output drop-in, don't do it." The problem would be heat build-up, as the Nitrolon construction of the G2 will not conduct heat away very well.
I'm going to move this thread to the LED section, adjust the thread title and close it, as the list of potential drop-ins is almost endless. Details of many of them can be found in this thread.