Yes, I worked with fresh frozen, and I perfected it. You know the "live resin" they sell in shops in legal states for high prices? Well from the pics I've seen it's sucky compared to the product I end up with by starting with fresh picked buds. Why do I say it looks sucky? Because it looks gooey or even runny, in other words it's a mess to deal with. When done properly, the end result is a solid, and not a "shatter" type solid, which also is not convenient to deal with because it splinters and flies all over the place, how is that convenient? No, the ultimate extract is solid but fudge type solid, not rock candy type solid. You can pick pieces off of it with your fingers and crush it up. Also, my product is washed with water, so all water soluble non-cannabinoids are washed out. Nobody else does that, thus, everybody else's extract has more impurities than mine, simple statement of fact, how could it not when it wasn't washed?
Now some might say "the precious terps, you might lose some by washing it". They're not water soluble anyway, all you're losing is water solubles, which are in no way helpful. Other extract makers just all copy each other so they never really developed any new methods or tried anything new since probably the 1980s, that's how primitive they are. Butane is not safe for anything used by humans, and CO2 pulls all kinds of extra crap out in addition to cannabinoids, and the finished product is really not very attractive.
This pic, which I posted earlier in a thread I made shows the ultimate extract. You can pinch a chunk off of that pancake and hit it up nice and conveniently. You would marvel at its lack of harshness, due to having a lot of extraneous crap washed out and the weed never having been dried. What is it called? Pancake Live Resin, or simply Pancake for short. Only the finest quality extract will form a pancake like that. That's how you know it's primo. Admittedly this pancake is a little oddly shaped, but it's possible to make a nice round one, I just wasn't trying that particular time. It might be possible to make something kind of similar with rosin but it wouldn't be this clean, you would probably hack your guts out.