I mentioned in "SureFire E-series Addicts Unite" that a titanium E-series tube is in the prototype stage. Still have a question for the drill supplier as $250 is a lot to pay for one drill if it cannot do the job. Once the drill arrives (and as soon as all current orders are caught up) the plan is to machine a handful to Ti tubes & find out the level of interest. If the tube is well received a Ti tail switch will be next on the list, followed by a Ti head.
I have a bunch of drawings for the tube but not a single one for the tail or head. Just have to wait & see what happens when the tube gets to the metal cutting stage & members have a chance to comment.