I know that as of 1.0.5 sentry does 175% dmg and no crit bit I was planning to try an (engineer) set up as I call it with focus on sentry as the main dmg dealer so I wanted to know what characteristics other than dmg does it take from the weapon (attck speed, life on hit, dmg converted to life, chance to stun...etc)?
From what I have seen/used not all sentrys are the same. Mainly chains of torment are the only one that acts different. None of the turrets benefit from crit chance or crit damage. None of the other turrets EXCEPT chains benefit from LoH. As for life steal I'm not 100% positive if it works for any or just chain sentry. When I was playing around with a high knock back % wind force I think I noticed the mobs being pushed away from the chains from time to time. I've not tested this properly and something else may have been causing the knock back. IAS effects all turrets.