I have X1 Producer which I just started using after a year or two.
I'm thinking up just upgrading to Artist since i really don't use many of the features of the software & the UG is very inexpensive. I just record myself & then add my arrangements. I have two questions.
1 - If I upgrade to Artist & decide later that I want to go to Platinum will I lose the ability to UG from X1 Producer which i assume would be less than an UG from Artist?    
2 - Since I already have Dimension Pro, Zeta, Rapture,Kontackt..... will they still work in Artist?
 
 

No
Yes

Thanks,
I think I'm going to go with Sonar Professional. It seems to be the same as Platinum minus a few instruments & plugins. I just hope it is solid & reliable.