I thought you were not supposed to use it with any other Thermogenics.Macro? Ulter?
You CAN but when you first start Thermorexin you'll need to find your comfort zone. To the average person it's very powerful so we recommend you try it alone and one cap to avoid any problems like nausea or dizzyness. Then work your way up.
I am using it with T3 but I can't get past 4/day and I like 3/day better. There are people who take 6/day with 12 clen (one pro I know 8 weeks out).
Some people don't "feel" anything. They are just resistant to the stimulation. There is a 140 pound female who is using 6/day and takes one at 8PM and sleeps at 10PM like a baby. HTF she does that I don't know.
It's not important to feel it. Even though it's more fun heating up.
You may not feel the heat if you're on a low carb diet. Like DNP it needs carbs to heat you up. If you find yourself taking extra trips to the bathroom all day on it, it's working.
Your workouts should be much better. Most people, like me, are reporting that cardio is a breeze and when you're weight training you feel like you could "do your routine twice today".
As far as other products with some of the ingredients...
Thermorexin has very powerful forms of the ingredients in it. Not the cheaper ones. It also has an uptake enhancer so you need to take less of what's in it and you'll get a higher bloodlevel.