I asked about this about a year ago.
 
I purchased Z3TA 2 on Steam, and to this day, Cakewalk Commander will install the Z3TA 2 DEMO for me, even though my ownership is listed in my account page on this site.
 
So far, I find that Cakewalk's DVD installers were superior.  They installed everything without requiring interaction once you entered your serial number.  Now, Cakewalk Commander already doesn't include third party installations like XLN's stuff, as far as I can tell, but why do I have to scrounge other sources even for Cakewalk's own software?