I've used it in a few products and I am currently using Thyrovex which provides about 900 mcg/day in 3 caps. I like it - you can feel it warming you up and I've had decent results with it in the past.
The last time I used it I was taking 600-1000 mg of 11-Oxo with 3,5 T2 and I dropped about 10 pounds in 6-8 weeks with a loose diet. This time, I am taking Thyrovex with 2 ML/day of XI-KT and the results have not been quite as apparent...but I'm not 100% sure yet. I am getting stronger, but not losing weight like I would have expected given that the KT should be stronger than the 11-Oxo....but I can fool myself into believing I am leaning out if I look in the mirror, even though my waist measurement has not changed at all.