Alignment rack? Nah...I'm welding up something to use with the two post so I can store them out of the way when not in use. I need to space for a tire changer and balancer
(evil thoughts...the wife will kill me if she knew)
Just did another oil change on the 4 post for the niece before she heads back to college. Another point for the 4 post...really, I think the 4 post is a winner for those who might drop the drivetrain once in a blue moon or don't mind using the jack bridge to do brake and suspension work. Although the two post allowed me to park one car under the other, the 4 post wins out since you can just drive up and put plywood across the ramps to keep oil and grease from falling on the car parked underneath.
The bendpak I have is bolted tothe floor and has very robust safety stops. It'd take a strong earthquake to cause concern.