The sharp knurling on the SureFire E2e will wear holes in you cloths very quickly. You will have to put something over it to protect your clothes. I have an E2e but switched to a C2 for that reason. I also have the cheaper G2; it is even more pocket friendly. But I have not been able to find a clip for it. I carry the C2 between my belt and pants with the clip over the belt. The belt keeps it pulled in tight and out of the way. A grab of the bezel will get it in operation very quickly.
Note I think this depends a lot on the pocket. I've carried a SF L1 in my front pocket of my Dockers type pants w/o problems for a LONG time. I've also carried a SF E2e in the same manner.
HOWEVER, carrying the L1 in the small pocket of my 5.11 pants (right thigh) quickly started to wear a hole in the pocket. This pocket seemed almost custom made for a light like this.
I've also carried an L1, E2e and M2 in front pocket of (close fit but not tight) jeans. The M2 is very uncomfortable there due to size, but the L1 and E2e were fine. In this case, I think the G2 and C2 would also have problems similar to the M2.
I also suspect carring the L1 / E2e in the back pocket would have caused a wear problem like the 5.11 problem described above. I also think loose fit jeans might wear more like Dockers.
In all, I think there are lots of factors:
1) how sharp are the edges of the light (e2e, l1 sharper than g2, m2)
2) how aggressive is the knurling (e2e more agressive than others)
3) how old is the light? (kurling mellows out)
4) how big is the light (m2, g2 much more bulky than e2e, l1)
5) how tight is the pocket?
6) what is the pant material?
7) what is the location of the pocket? (are you going to sit on it, does the location cause the light to move around a lot?)
8) how heavy is the light?
You get the idea. In the end I think the knurling is a factor, but it is only a factor. In some cases it can be offset by other factors (small size, light weight), or it could go the other way and be a problem.
If it turns out to be a problem, you can also take the edge off by hand. I'd try maybe rubbing it down with mud as a first step.
Just a few thoughts...
-john