I've had no bad experiences with it, but don't let anyone tell you its painless cuz its totally not. As far as people saying it goes thru a slin pin--I've heard of sources claiming this, but honestly I don't know if they are underdosing or what. Cuz I have trouble getting it to go thru a 23g pin at times and my gear comes from a very old, very reputable source.
Anyhow, I actually love test suspension just prepare for the pain that comes with it. Sometimes when I'm goin out I will pin 100mg just to get hyped up. I can actually feel it working within minutes--so thats cool. Just be careful with BP--since there is no ester sides can get nasty real quick.