.

I installed the X1 trail and once it expires nothing happens to 8.5 It just sits there waiting for you to pay the money to activate it, There is no reason to uninstall it unless you are anal retentive about hard drive space. 
Havn't tried the X3 trail,, just going to buy x3 Studio and be done with it. 

Thanks Noel (and others who've shared their experiences), that's very helpful and exactly what I wanted to know.

http://forum.cakewalk.com/X3-Demo-killed-my-85-m2980458.aspx
 
Seem it did cause a big problem for Randy  have you gone forward yet,, better read his thread first.. 

Cactus Music
http://forum.cakewalk.com/X3-Demo-killed-my-85-m2980458.aspx
 
Seem it did cause a big problem for Randy  have you gone forward yet,, better read his thread first.. 

Right now with that issue, it's hard to tell what is at fault (Windows or Sonar 8.5, it's probably NOT Sonar X3 that's the issue although installation or removal of the demo would have triggered it, and probably took away a wrongly referenced C++ dependency). Either way it just goes to prove you should always have a backup strategy or face the consequences should they happen. Anyway we shall see what happens with the OP.

Cheers..