Mechanical vs. Air Lockers??

I just want to thank all who contributed to the discussion Lockers vs. Winch.
I've decided to go with a rear locker in my V6 120.
I get the feeling that because I’m predominantly traveling on tarmac then a mechanical locker will get quite a lot of wear?? Where as an Air locker is just disengaged until you need it. But there are price advantages with the mech. option.

So lets here it Prose and cons.