LSD and DMT are potentially the two single most important substances in the world; if mankind ever wants to grow beyond the point of warlike apes.
Expand and diversify. Understand; love is the law. The universe is on track.
To say acid is bad is like saying a hammer is bad - You can build things or destroy things. The hammer is not inherently good nor evil; only the use to which it is put.
Conveniently; it's rather hard to put LSD to bad use, though a lot of people try. It is not what one would call an 'abusable' drug; those who find themselves fiending for the experience are clearly blinding themselves to what they should be feeling. These are the saddest of all minds, and should be walked alongside until they can get past the vapour rumours of life and time; and stop lying to themselves. Remember - It's no about how many tabs you can take, it's about how many tabs can take you. Just because you had an unpleasant experience doesn't mean it was a damaging or bad experience. You have grown; you have survived and you have pushed the boundaries of your conciousness. You know more about yourself then you ever would have without it.