Quote Originally Posted by Anonymouswizard View Post
EDIT: yeah, 3e and 4e are mostly compatible, points costs have changed but things like technology translate with maybe a couple of minutes of work. Psionics works completely differently between the editions, and it's better to use a 4e psionics system because they're balanced better.
Armor works much better, as the removal of passive defense from (most, at least?) armor means that you don't have the situation you did in 3e where you were comically easy to hit if unarmored, in addition to the DR properties.