This seems logical since it's more like a physical console, but I have had it at the top for so long, that it looks weird at the bottom.  Just curious.

I have seen screen captures with it placed at the bottom. It looks a bit odd to me too. I think it is truly a case of personal preference. There is no impact on Sonar's operation in either case. 

I used it at the top to start with but with a neck fusion and the monitors sitting on top of four space rack gear boxes,putting it at the bottom made things very easy for me......
 

I have it floating and only have the Time module showing by default. When the Control Bar is fully open it uses too much real estate. I've found I tend to use one particular module at any time. Activating that module is worth the trade off to get the screen real estate back all the time.

In doing this it's important to use keyboard shortcuts so you don't need to use the Comtrol Bar too much.

You may already know this Mike but c will toggle it on and off. Also F11 will use all the screen for the TV. 

Mine's at the bottom.
 
In pre-X versions it used to be possible to spread the Control Bar over more than one single row. I had them split, one at the top and one at the bottom.

I've always had the Control Bar at the bottom of the screen. I like to have my monitor set at eye level so I'm not looking down too much. Seems more natural now to glance down a bit to the Control bar, than to move my eyes up to the top of the monitor. Certainly it's whatever suits your studio ergonomics, and whatever you've gotten accustomed to . . . I think every Sonar video, and screen shots I've seen have it at the top, so It seems the majority have it up there ?

For touch screen , it s a must ... Here s when i do use it like that ;)

I have mine at the bottom. Been doing it for a while, and would not change back.
All the best.

Mine's at the bottom, too - since many many years. I never had it at top.