Impurities can skew results, introduce confounding variables, and even pose risks to research subjects
It serves its intended purpose reliably in our daily lab activities
If you find the 45 unit mark uncomfortably small to read, the honest options are (a) use a finer-gradation syringe, or (b) follow a protocol built around the 50 mg vial, whose larger draw is more forgiving not to freehand a bigger volume from the 10 mg vial, which would silently overdose relative to the documented figure
Reviews typically cant control for confounders (diet changes, exercise, stimulant intake, sleep, stress, or other supplements), and negative experiences are often underreported