any information on wich variant were considered for the X4 beside the A1a (hobby boss put 4 X4 under their A1a/U4 but I'm not really sure it would work well)
Also wondering if the X7 Rötkapchen was considered for the 262
http://modelarchives.free.fr/photoscopes/X4_P/index.html (french article on the X4 and X7)
The X-4 would likely have been most effective against bombers while they were locked into their bombing runs. I suspect they would also been useful against aircraft taking off and landing from airfields.