I've installed a few different makes including a PJ and AEM but now run an AIRAID and can tell you that they're all pretty much the same. What I like most about the AIRAID is that they are built really well and have a more factory finished look to them. If you live in CA, they do come CARB compliant too.
With this being said , is there anything you don't like about the aem? What do you like about it ?
One thing I like about them is that it's going to allow me to install my PSC steering assist once all the kinks are worked out.