Also, to me the difference is that the hopshot product is actually kind of like hops distilled down, just having left their solid cone mass behind. It literally tastes and smells like a hop on steroids. So you are getting more than just alpha from the addition, you get all those other aroma and flavor compounds that hops have too.
Here is the product that hop union sells. http://hopunion.com/CO2-hopextract.html
I'm pretty sure that's the exact same thing that Northern brewer packages into the syringes. They wouldn't divulge their supplier to me, but I've done some research on this. Pretty close to 100% sure that it's what Vinnie and Lagunitas use in their imperial IPA's.



