Thanks everyone for help!
So if I move to PT11 with no PT 10, is it better to move to Mavericks (which version?). Or Mountain Lion will work great too?
I see PT11 compatibility grid (below) and I get confused, too many options
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System Details:
Host: iMac 27" QuadCore i7, 3.4GHz/32GB RAM/768 GB size internal SSD HD. OS X 10.8.3.
Interface: Avid Mbox 3 Pro.
Monitoring: Yamaha HS80M + Avantone MixCubes.
Two external HD (7200 rpm, 64 cache): Buffalo DriveStation (for audio projects) + OWC Pro (for instruments' libraries).
Instruments and plugins: NI Komplete 9 and East West Complete Composer's Collection 2 and other.
Moved from Cubase 3 to
PT10+MboxPro. Very happy with PT10!
