quality stuff.....Lets say I want test. But I don't get it because the quality scares me...I'm not even thinking PED/AAS just plain test.
There was tons of garbage test out there 10 years ago, but from my perspective nowadays most tests from UG are legit. Whether it is clean or not is another story but for actually dosed properly, a bad badge seems to get exposed instantly and most UG sources are making good on their end.
But to be 100% sure, like the guys above say, trust your sources and do lots of home work. Look for reviews and get feed back from users etc.
I have to only smell a product to know what is inside it but I am experienced and have been around but someone who is just starting out has to pay attention how their body reacts and know what compounds make you feel a certain way.