If any of you have the UAD1 card, u know that it is not supported after Dec 31... can't add plugins, can't transfer it, etc.  They are offering a $200 voucher for plugins if I buy a new card, and all I can afford is the solo core.  Is it worth the money, $300?  I do like and use the compressors in UAD1.  
Oh, and if anyone knows, since I can't change the authorization file, does that mean a computer configuration change would require a new authorization, rendering the card unuseable? 

The authorization file for the UAD1 is tied to the card itself, not the computer, so you do not need to worry about what computer you install the card into.
 
As for a UAD2 being worth the cost.. That's up to you of coarse, but I think it is worth it. Not only will you be able to run the newer plug-ins from UA, but you will have about 3x more processing power from the UAD2 than the old UAD1. Keep in mind though that some of the newer plug-ins can use up the entire processing power of a UAD2 Solo.

if you just run the older legacy plugins the solo is fine .But the new plugins require a lot more . I thought having one Octo eight core card would be all I'd ever need ( I was maxxing it out right away ) ended up buying another one.. Your computer can run up to four cards but most motherboards don't have enouph Pcie  slots . If your planning on getting more plugins later you can Always add a Octo  with that solo