1-you will get tested,so staying on for 5 years isnt going to work.
2- you wont need to be on all that time to achieve your goals if you make the most of your cycles while on(ie eat,train,rest properly,followed by PROPER PCT)
3- you may be able to still have kids,you may not,nobody can tell,but some guys have gone sterile on cycles of under a year,so the risk is always there,can you deal with it? if not stay away from gear because we dont need anyone else running to the media crying when they can have kids blaming steroids when they knew it was possible you can go sterile.
that is all,have a good day