Thanks everyone for the great info! In response to how the light will be used, I work a evenings in a maintenance evironment and the light will be turned off and on alot and just generally be used in a rough environment. Thanks again for all of your help!
The Eagletac will resist very well any wear from operating the light. Moreover, the tail switch assembly is available separately would you need to replace it at some point.
However if you also foresee stepping on it with work boots and other similar "abuse", check the other suggestions here, you ideally want a nearly-cylindrical body of constant diameter, with thick walls. If the middle section is of smaller diameter than the ends (like the Eagletac), if you step on on the light in the middle, it will bend.
nap.