I've used both pre and post workout. Mainly used to help with a few injuries. I personally like it better pre.
A few years ago when not working out, I would weigh around 160. 5mg of IGF, some rehab exercises, and a few years later I walk around closer to 180. BF% might be a point higher though. I'm buying size 34-36 pants but my waist is 30-32 which kinda sucks. Too much junk in the trunk now.
Upper body has gained some size also despite not doing any injections there since my shoulder injury a few years ago. Didn't use to gain muscle but it certainly does that. Only used pre workout/ rehab. Never noticed any slimming effects but then again never had a diet or exercise program conducive to such things while on.
Keep it in the fridge.