Yep. Was buying something else and somehow a Solarforce L2X Extended Host jumped into my online shopping cart. Before I know it, It’s sitting on my buffet with no drop-in. So now I need some options for some quality drop-ins for using with 2 X 18650’s. I’d love to have a good throw module and one that’s sheer lumens.
I’ve seen a number of you state that the SF drop-ins are not that impressive, so I’m very open to any suggestions. 
I have a Surefire P91 xenon drop-in in my cerakoted L2X. The output is impressive for only 200 lumens.
When using a Surefire drop-in in a Solarforce host, you will need the outer spring from an aftermarket drop-in.
You should consider replacing the reverse clicky switch with a McClicky.
Why replace the switch?
I have a 1,000 lumen dropin in L2m works great. From Kaidomen.
The switch in the L2X Ext host is louder than normal when powering on/off.
From my experience, Solarforce reverse-clicky tailcap switches have failed more than all my other clicky tailcap switches combined.
SolarForce has several XML drop-ins that will run on 2X 18650s, look for the “high voltage” models. A “thrower” drop-in would be the XRE emitter single or multi-mode models from Lumens Factory, LightHound had some of those in stock last time I checked. Nailbender or Vinh can make you a single mode drop-in for 2X cells, I don’t believe that either has a multi-mode Hi V driver yet but I may be mistaken.