Okay, so I have been using MC4 and MC5 for years now, but as I get more involved in recording projects, the limit on number of audio effect, tracks, etc as compared to Sonar is becoming a problem.  I just saw that we now have X3, which apparently is a $49 download for any registered Cakewalk customer?  Are my eyes deceiving me?  And is it worth it, for those of you who have used both MC and Sonar?  Also, are the Sonitus effects included in X3 (like the reverb and EQ) pretty decent?  I've become rather attached to the Studioverb and third party effects like George Yhongs Limiter and KarmaFX EQ....is it time for me to "get with the times", so to speak? Lol.

Also, I am looking at upgrading to a Lenovo desktop computer (Win 8) with the Intel Pentium Dual Core G2030 (3 GHz) processor, 4GB DDR3 RAM, 1 TB HDD.  Sufficient to run X3, or any version of Sonar for that matter?

Apparently so.... nice price....
 
It is, I'm fairly sure, the equivalent of what I have. I grabbed an upgrade/cross grade from MC to X1 when it was the new kid on the block. The version is the lowest of the X1 series called X1 essentials at that time. 
 
I'm guessing X3 is the same deal.... basically the "essentials" version of X3. Still a nice upgrade for that price since it does allow more active working inputs than the 2 MC allows. There will be some other "goodies" included as well....
 
If you're looking for the expanded capacity, that's a good deal.

Sorry, I'm not seeing the $49 price. Where is that advertised?
 
Upgrade from SONAR X2 Producer$149.00Upgrade from any SONAR Producer$199.00Upgrade from any SONAR Studio$299.00Upgrade from any other SONAR$399.00Upgrade for any registered customer$449.00

There are three different versions X3, X3 Studio and X3 Producer. The $49 upgrade is for all registered users to upgrade to X3 the last selection on this page. The product feature list comparing each version is here.