I have it all the time. In very large quantities, opium can be a bit trippy, slight melting walls, etc. Also lasts a long time and takes orally as laudanum almost 2 hours to really peak.
VERY Itchy compared to anything else even if you have sky high tolerance to any other opiate.
You can only get laudanum as a tincture with the narcotinevremoved so no nausea.
Also, itching starts about 12 hours after peak. And half life is comparable to methadone.
Worst part is that although you can still get something off of your doc, it has the most cross tolerance of any opiate because it literally contains dozen(s) of alkaloids. After a few days of use in the 200mg range daily (which is really 200mg of morphine but who knows how much other alkaloids), I get some WD even when switching back to 200mg oxy daily. Shivers and general malaise mostly, and definite depression. What I get is pharmaceutical so no adulterants.
I need this as medicine, but once in a while end up taking a 200mg dose because I am an idiot. I know that I am going to pay for it later, but as lo g term pain patient, sometimes I run out because I have been at same dose of regular meds for a decade. That's when I take more than I should... Prescribed dose is like half a ml (which should only be 5mg morphine) . Speaking of pay, out of pocket it would cost at least $10 per mg. So for example 500ml would cost $500 if I had to pay out of pocket (yikes!)
It also varies a LOT by time of year and batch, even from one of the only 2-3 companies licensed to produce it in my country. Color is different, taste is different, and DEFINITELY the amount of itch it causes is different, so I am guessing that the alkaloids besides morphine in it vary widely. Even color varies in terms of how cloudy it is. I insist pharmacy shake bottle dispensed from or a lot settles to bottom of the larger container it is dispensed from.
Disclaimer : I NEED this so not condoning irresponsible use (going over 1ml a day). It's not a toy.
Overall, it is not as euphoric as oxy, and does cause sleep disruptions sometimes, but it does have delerium unlike other opioids which I guess some people would want to experience, but if people 200 years ago had oxy or any of the other options they have today it would not be anyone's first choice of opiates.
I never smoked it, this is oral. And everyone would DEFINITELY experience this differently because of the full spectrum of alkaloids it has, but I would not obsess over trying to find it or feel like you are missing out on much after the first time you experience it.