Sure thing, if the application you are deploying works on it.
Main thing to note is that EAP6.x is Java EE 6 certified and WildFly 8+ is Java EE7 certified.
Which might cause some differences in deployment of your application.
Thanks for replying Tomaz. Does this mean I should try to deploy an earlier version of Wildfly, one that's Java EE 6 certified? This is a closed production environment, so I'm not too concerned about "security issues" necessarily. There's no backwards compatibility with Java EE7?
Earlier versions seems not a good idea as you'll miss all the current fixes.
One issue is that WildFly does not support EJB2/CMP, but if you don't have it ....
And other components might be newer which might cause issues as well.