kitekrazy1
 One of the biggest differences is the lack of 3rd party tutorials for Samplitude.

kitekrazy1 - Look here.
 
To the OP: I bought Samplitude X3 Suite and Studio One 3 when Cakewalk folded last year. They are both terrific DAWs. It will depend on your personal style and preference, but you can't go wrong with either. Of course you have to understand it will take a while to get good at either of them, so you have to spend time on your decision. I can say this, if it helps: Samp is the geeky one, S1 tries to be simpler to use. (Full disclosure: I like geeky stuff.)

In the end, I decided to let both deals go by and wait to see what the Samplitude X4 Pro Suite is like. I liked what I saw in Samplitude but will play with the X4 demo when it's released.
 
I did buy Helix Native on sale ($70) as it seemed silly not to have it along with my Helix LT.

It appears the X4 Pro and Suite are available as of today. Sound Forge Pro 12 is NOT included and the list of feature enhancements don't do anything for my usage (simple audio recording), so I guess it was smart to wait (for me, YMMV). I did like it well enough that I will keep an eye on it a year from now and see if it can be purchased for $150 or $200 next holiday season. 

The upgrade price is $149. There doesn't seem to be all that many improvements that would interest me. I don't work with take lanes. Support of up to 32 processor cores doesn't interest me. Not to mention the upgrade price is the same as what I initially paid for the whole suite in the first place. Umm, no thanks...