MY experience
I spent 300USD from a reputable USA pharmacy not a chinese source on 10mg and IMHO this provides no recreational value. I noticed people were consuming it quantities such as 150mcg. If it is only 30X40 more times potent then morphine, why such small dosage. I started with 500mcg squirted under the tongue. Waited an hour nothing. I proceeded to squirt 1mg (I measured the powder into an oral solution) and maybe experienced a slight relaxation but nothing I could rule out from the placebo effect. However I suppose I have staples in my right chest because I broke my clavicle a week ago, and I did not seem to notice the regular pain.
So just to make sure it didnt have a long onset, I measured out about 500mcg of the solution and IV'ed. The first time I did was a feeling I never had before, extreme flushing, my heart pounding in my ears. Not euphoric or really pleasurable. Over the next days I experienced with doses intro-nasally, under the tongue, and IV around the range of 250mcg to 1mg. The 1mg injection was the same feeling, no euphoria just a tingly palpitation almost as I can imagine a heart attack would feel like. So after 30 seconds, I had a suboxone and slipped it under my tongue to you know, hope the naloxone would counter it if I was in any danger.
In conclusion, to me this drug has no recreational value at all. The IV rush lasts maybe 30-90 seconds then nothing. The other methods of administration I didnt notice anything stronger than a 5mg dose of diazepam.
Don't waste your time.