I think everyone will agree that using a tie-rod end would work on a control arm. I also think everyone will agree that using poop-pipe works on a control arm, but when the rig starts seeing crazy stresses, I'd prefer not to have that under my rig.
I have no idea how strong those ends are. They could be the bee's knees. Once again, I applaud you for thinking outside of the box. If instead you are looking to save some greenbacks, I'll give you these links.
http://www.pirate4x4.com/forum/showthread.php?t=358938
http://www.pirate4x4.com/forum/showthread.php?t=319739
They are cartridge joints, similar in style to a johnny-joint, and are less than $35 a piece.