It’s called a P60 sized drop-in, because that is a Surefire size designation for a reflector-LED-regulator assembly that also fits many different other manufacturers flashlights. The Solarforce drop-in is advertised as 290 lumens (seems unlikely), maximum. The five modes are: strobe, 3 levels of brightness and S.O.S. It was $27.99 USD plus $3.00 shipping. It showed up today in the mail and I was shocked, because delivery from China, where the vendor is located, took only 10 days.
For a comparison test, I used fully charged Ultrafire RCR123 batteries and Ultrafire 502B flashlights with switches replaced with Judco SPST 519PB-ND I bought from Digi-Key. The other P60 size drop-in was a generic Cree P4 module. In the first beamshot, the difference is brightness is minor. I tried another Cree P4 and it put out much less light compared to the Solarforce R2 drop-in. The third beam shot uses the first two modules, but is underexposed 1.5 stops to maximize the visual difference in the two beams.
So did I find a brighter light? I have the feeling I did. I’ll have to check it with my light meter and compare the EVs.
My beamshots were done with a Nikon D70, Nikon 50mm f1.4 lens. Exposure information: ISO 400, 1/30 sec, f2.0.