I'll address that one, if I may, GOD.....
First, piperazines are crap.
Once you press them, and they leave your hands, they WILL be passed off as ecstasy, to some poor unsuspecting trusting person, who will feel like shit and wonder why you did that to them.
Generally, a person wants to press a pill=for commercial reasons, because it's just about impossible to cut a pressed pill, thus it is the preferred method of bulk retailers.
CApsules are easy to cut, and when the trust isn't there ( and it NEVER is when you're selling to strangers) they will always be tampered with.