The technology does have limitations. AAE states in their literature that the Stealth Technology System's minimum effective distance is 20 ft for both Visibility Stealth and IR Stealth. In other words, the observer or detection device has to be at least 20 feet away from the cloaked object. 20" is still awfully close for someone not to be able to spot an APC or MBT (Main Battle Tank).
Previously on this site we indicated that metamaterials are being developed for invisibility