I'm wondering about this as well. I've always responded well to the E/C/A stack, yet clen did nothing in terms of losing fat. It just kept me from gaining any post cycle. When I tried it last summer for fat loss, I got nothing from clen except jitters.
However, I have to see a cardiologist soon for a genetic heart palpatation that comes and goes. Nothing serious, but I'd rather be careful.
I was looking at H.E.A.T. and Lipo 6 without the e in it. Yohimbe hasn't been a problem in the past.
There's a lot to read here, admittedly, but I'd still like some more recommendations.