Libs are considered primary targets because of the Zephyr and Dalton for most lockons. I don't believe it is purely just because they are vulnerable due to just lockon time, but the other issue is the lack of 'maneuverability', IE they linger in the open more than the ESFs do. The Afterburner, even without the fuelpods, tend to help the better ESF pilots get out of most troubles by not staying in easy LOS of both flak gunners and lockon weapons, however, for the liberator to be 'effective', it has to have the belly 'above' the target more than putting it sideways. While you can fire the gun, with the proper ballistic to make it so the dalton is no longer the easy 'OHK' on ESFs, it also makes hitting ground targets a little less 'point and click' firing. The Liberator in and of itself is just 'slow' and a big target that vehicle stealth doesn't really buy it much support in this regard, where as for the ESFs with the 'faster' and better maneuverability, stealth can buy ESFs a little more breathing room in their pass more so than a Liberator or a Galaxy against ground units. Now against air... Stealth would probably make it a little easier for the liberator to be an Anti-Air Libs, allowing it to react better against ESFs, as the ESFs have to pick either lockon range or lockon acquiring, giving the Lib pilot a chance to readjust his lib to allow the shreader gunner to F the ESF. That is the ONLY place I see where Stealth would help is to **** the enemy Air A2A Lockons more than the ground ones.