FYI...I was just the opposite. I used the liquid for 9 years, had good progress, but like everyone, application could be messy. Anyway when the foam came out with all the hype of how more effective it was and how easy it was to apply just had to go for it.
I really liked the way it made my hair look, and it was a snap to apply. In my mind I was really glad they came out with it. In about a months time I began to shed, similar to how I did when first using the liquid way back. I thought this would be good and I would end up with even more hair, sounded really good to me. Unfortunately the shed tapered off a bit but continued, this went on until one day I finally realized I was really loosing my hair again. I had no clue how much I had lost in my crown until one day I saw the back of my head in one of those security cameras in a store. I could not believe it. I got real desperate and went back on the liquid and hoped for some improvement. Nothing seemed to improve until 2 months later, just a bit but better than it was. I have remained on it since. I am not sure its all back yet, may have lost some due to the time I was on the foam, but I am pretty happy now.
IMO...foam is not nearly as effective as the liquid, just like the study indicates.