Most of those who experienced any effects, were likely obese or had a relatively high BF%.
DaBuffguy is correct, CLA is effective and the studies are there to prove it, however, if you're not in the higher % of bodyfat, then you're likely to see little to no benefits. Dabuff, it would be interesting to see if the people who gave you positive results fell into the higher BF% to those that gave you negative reviews of CLA.
However, There are lot of people who have seen an incredible leaning out effect with other fatty acids. Arachidonic Acid has been extremely helpful to many people on a cut. You could look into X Factor by Molecular Nutrition. I'd be able to answer any questions you had pertaining to this supplement.