For throw, IMS20. I prefer the McR-18 though, it provides a more useful beam than the IMS20 but it really depends on what you want the light for.
All my minimags have IMS20 & McR-20s. BTW, the IMS20 does not fit the minimag head unless it is bored.
Thanks Dark Zero,besides boring the minimag, will I have to bore the Ims20 or McR-18 to fit the cree led?
You also might try the Fraen reflector, it will push right onto the emitter, so no focus, but it is a bit narrower.
You can see it on one of the Minimags I modded, but would probably work with that drop-in as well.
https://www.candlepowerforums.com/threads/194179