Retrofitting CMM

I am in the market for a used CMM capable of 40"X x 60"Y x 24" Z. Scanning capability is a crucial aspect of my inspection. My budget is approx. $ 90 K US funds.
Most machines I find available within my budget are touch probe or have been upgraded to scanning. Can anyone provide any personal views associated with upgrading a machine, mechanical vs air bearing, preferred software etc.

Thanks

 

[Umhoefer]

Dear Old IE,
Have you checked out

http://www.atiquality.com?

They have several new and used units.

Regards,

G. Umhoefer