I do not understand what people have to complain about the smell or taste. Perhaps some have not yet been confronted with many different smells or tastes but the smell / taste of Macs powder counts for me is definitely not the worst and can not be definitely described as "hellish" taste.
The smell is Ok and the taste as well. If you mix the powder with juice or a smoothie, it is to get it down no problem. As some so-called specialty or drugs are significantly worse.
For the effect, I can not say anything but thousands of reports and several studies are probably not err alone and the composition of the plant is very interesting.
So I'll take my powder diligently to me and stay curious how the effect is.