What to you think about GNC's 1 - AD ??

Hey fellas,

I wanna ask you a question about 1 - AD, and especially the ones that GNC sells.. I believe TwinLab makes 'em, I never took them I just wanna know if they work..GNC usually overprice their stuff, but a friend of mine works there he said he could give me the bottle for like $20 bucks.. so does their (GNC) 1 - AD work, how long does it take to kick in..and I heard if you combine 1-AD to 4-AD it works better...

Thanx