I have the Derek Weaver 4 post lift like James.  Mine is the one that has an extra foot of height, giving 6-8" of clearance under it at max lift.  This is important if you want to be able to park a car on it and be able to walk below it.  Unless you are taller than 6'-8". 

I also got the shortest (wheelbase length) and narrowest one they had in 7,000 pound capacity.  I have had my Dodge Ram 1500 on the lift with no problems.  Mustangs fit perfect.

The Derek Weaver website has the exact dimensions of the entire lift.  To me, that was important because space was definitely a factor.

On a related note, the Chamberlain garage door lift that operates directly on the door's spring shaft works great.  Thanks to John Ha for recommending that lift.  Since my lift is only 7' away from the door, there was no room for a conventional overhead garage door opener.

Pic shows how high the lift can be positioned allowing use of space below.  12' ceiling lets the Mustang go all the way to the top position.

Then there is the single post...

Typo on the inside tire (tyre for the British cars) or Typo on the Garage Door opener?

sooo in following the mustang Steves rule

1)  build 4 bay shop with thick cement floor ant 16 ft ceiling 
2) buy two lifts (one each style)
3) install correct doors and openers prefer wind up at door top with nothing going across ceiling
4) rethink #1 for larger and #2 for maybe another four post for car storage one on top of the other??  
5) then maybe you'll get to review Mustang Steve rule again 

 

When I built my shop, I had originally planned to have a 2-post and a 4-post.  2-post for more mechanical work and 4-post for more long term storage.  Then the town told me that I was too close to the set backs and I had to shrink the size of my shop.  That left me with having to decide: 2-post or 4-post.  After thinking long and hard about it, I decided that most of the time the lift is going to be used for storage and a 4-post is just easier for that, so that is what I went with.

After researching them to death and talking to multiple owners and different vendors, I wound up going with a Direct Lift.  http://www.directlift.com/Four-Post-Lifts-C9.aspx

They are made by Rotary but are less expensive than Rotary, Bend Pak, Greg Smith or any of the other big names.  The company that delivered and installed it for me services most of the lifts in the commercial shops in my state and sells Rotary and Bend Pak and they told me that from what they could tell, Direct Lift was just a re-badged Rotary.  And with the $$ saved by going with the Direct Lift, I bought two of the hydraulic sliding scissor jacks, which are fantastic and make it really easy to change tires, do brake and suspension work, etc.

The other advantage to a 4-post that I didn't appreciate when I first got it is how useful it would be in working on my shop.  My shop has a vaulted ceiling and at the peak it is about 19' high.  At the moment, I am installing corrugated metal on my ceiling, which would be almost impossible to put up without the lift.  I've got scaffolding set up on the lift and I raise it up to where I'm working and then can easily work on the ceiling.  And when I need to move to another section of the ceiling, I just lower the lift onto the casters and move it to a new spot and keep on working.  And it rolls really easily on the large rubber casters.

All in all, I've been really pleased with the Direct Lift.  And I too have the side mount door openers with jack shafts and they work great too.