I looked at these for a while, then I looked at the ingredients and looked into their benefits.
Most of them have:
Omega 3 (or 3-6-9)
caffeine
green tea
some form of pepper
So I started taking omega 3-6-9 tablets and eating more oily fish + ground flax on my porridge
Drinking more black strong coffee in the mornings (which suppresses my appetite until lunchtime)
drinking green tea in the afternoon and taking green tea extract tablets in the morning – more caffeine)
and I always have a lot of pepper.
Also been taking whey protein isolate after weight training.
Lost a couple of lbs last week, and have steadily lost 1 stone since January, but I am weight training & running 2/3 times a week, karate twice a week, & cycling 8 miles a day. I have almost doubled my bench press and squats in 2 weeks too, so working for me so far.