Yep, better than hop pellets - all the flavor and no hops screens! I do not know how much hop extract you would need for a 5 gallon batch. It would be fun to try the canned extract. It is $21 for a 3 oz can of pure hop oils.
Supercritical CO2 Nifty! Take CO2 up to 1200psi and 100F, and it is just barely in the range of a supercritical fluid.
Here is a concise and understandable demonstration of the supercritical process done by a person in his home machine shop:
Watch when he shakes the acrylic vessel and the liquid and gaseous CO2 mixes to create ... something bizzare ... it's supercritical!
Here he extracts caffeine from green coffee beans
This is a commercial sized process with a 65 ton vessel, extracting caffeine from dried tea: