Problems - can fuck with sex drive (returns to normal)
Can change things in your body - Red Blood Cell count (kept going higher and higher slowly until i came off), Liver values (mainly due to eating especially too much protein) Other things but that's all i had but then again Dennis Newman ended up speeding up cancer?
More body hair growth, speed up Male Pattern Baldness
As for how bad it depends upon the person, dosage, length of time on, how young you are when you come off etc.
Totally agree you should at least train 3 years naturally with which you will gain 95%+ of muscle you could gain naturally. From there naturally it's all maturity and density. Why juice if you can gain it with no problems.
As for Croatch, too insecure. Bigger than most juicers out there and still insecure

.
When you are on gear you hold more fluid and if you have a good level of muscle it fucking sucks, i could not get my face to not look bloated unless i was dieting at low BF.