Since I was a mechanic before, I wouldn't have anything but a 2 post asymmetrical lift if given the choice. The 4 post is nice if you aren't working on the suspension, but even the front end techs will take cars off the 4 post lift when they need to work on control arms, etc. Always better to have more room to work and it seems the 4 post just has the ramps in the way despite having the auxiliary lift jacks.
Perfect example, try putting coil springs up in the frame pockets on a C3 if you can only get it a few inches up off the floor. Sure you can fight with spring compressors, etc. but having that room to work is amazing. Another thing to think about is getting out of the way if something happens to slip or fall out of your hands while installing/removing. That's much easier to do on your feet.
This is my biased opinion of course, but I have worked with both extensively. and I've also worked with both symmetric and asymmetric 2 post lifts. For my money, it would be 2 post asymmetric with nothing on the floor but the floor mounts for the post. My first lift as a mechanic was symmetric and the controls and lines went across the floor between the posts. Rolling a dead car by yourself over the hump is no fun!
The fun safety message for all of this is, no matter what you do, ALWAYS lower the lift down onto the safety stops BEFORE starting to work on the car while on the lift.