I'm a bit confused. I want to get sonar and I want the artist version for the 9.99 a month for 12 months. What exactly is the member ship for? it is confusing to me. Saying there is a discount price after 12 months. I have a steinberg ur 22 that I will be using with sonar and I hope its compatible. I was thinking of getting elements 8 from a voucher there offering but sonar has the monthly plan and I have used sonar products in the past and I like there set up so I'm more interested in going with them. I just want a full version of artist for now.. Then I will upgrade to the pro level but I don't think I need platinum at this point. Its only me in a home studio. 
 
Sorry IF this is in the wrong spot.. I was trying to email support but It kept asking me for a serial number or order number and since I had neither I figured id post here. 

No, right spot I suppose. 
 
The $9.99 a month is the payment price for SONAR Artist - you pay that and at the end of the 12 months you own it free and clear.  Over that year you'll get updates/bug fixes, plus whatever other effects/synths Cake synth adds.  Or you could buy it for $99 upfront and get a year "membership" with the same updates and effects/etc. and save yourself about $20.
 
The Steinberg interface should work - that has more to do with your PC than SONAR, although some software may run on one computer and some won't.
 
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