We go through quite a bit of CLA products on a daily basis all featuring Tonalin CLA as their primary source. Like was stated above, normally users report that it does take longer to see a result since it is non-stimulant. Also, remember that CLA is a body toner, specifically around the mid-section, so weighing yourself isn't the best way to track results; instead, measure your waistline, it will help you lose more inches than pounds.
Just make sure you are taking the recommended does of at LEAST 3.5g of the CLA a day.