I put the patch on saturday 08:15 AM since I read that it took a while to peak and I didn't want to peak in my sleep. 4 hours later I started to feel the fent and it was very sedating. Note that I was at work (low intensity) when it started kicking in so I had something to distract my mind with. From the moment it started kicking in, I felt that the effects got stronger every hour until like 16:00 PM. The main effect I felt was sedation, I felt lethargic as fuck but I could still function pretty well, my eyes were hanging kinda low tho. It also felt very warm, not the warmness that oxy could produce but it was pretty close for me! Very comforting and nice warmth. Euphoria was minimal, it was there but not that full blown euphoria that I felt with oxycodone but I was for sure happier and it did feel good till a certain point. I got home at 16:30 PM and decided to have a very very small bowl of weed (one popcorn kernel big) since I was on a T-break (12 days in) and I didn't need a lot. I wanted to smoke since weed potentiated oxycodone for me by a mile and I was curious how fentanyl was with weed. Smoked it, and I felt very very very tired after that. Struggled to keep my eyes open and I just felt like sleeping. I can't really remember the feeling now but I know it wasn't anything like an oxy nod and it was like my body was telling me to go sleep. Could be that the fent was peaking even more or something with weed but idk. Fast forward to like 20:00 PM, it felt still very warm and I felt less sleepy but still very sleepy. I noticed that I felt very nauseous when I didn't eat for a while (6 hours or so) and eating something did relieve it. At around 21:00 PM I decided to go to bed since I was too sleepy and it was weird. I wanted to sleep and my body felt like sleeping too, but I couldnt fall asleep. I noticed that my respiratory rate decreased and I sometimes forgot to breathe so I was manually breathing the whole time I was trying to sleep. Even though I felt so sleepy and I couldn't open my eyes, I didn't fall asleep. I thought I slept and it was like 00:40 AM when I looked but it felt very weird like I didn;t sleep. Fast forward to 06:00 AM (sleeping I think) and I felt horrendous. Awfully tired and my watch tracks my sleeping (idk how reliable it is since how tf can a watch measure my REM) but for the first time ever in 2 years the thing said that it couldn't track my sleeping record so it told me basically that I didn't sleep at all that night. I had to wake up a bit and felt very dazed, no euphoria, still a bit sleepy but I could keep my eyes open and the warm feeling was still there but not that strong. I got out of bed at chilled a bit until 08:00 until nausea hit me like a truck. Went back to bed and closing my eyes relieved and laying there relieved my nausea and I slept until 10:00. Got out again and that's when I started feeling very very nauseous and the sleepiness came back again. I took the patch off since I felt too ill and went back to bed. I initally didn't want to take it off since I wanted to experience the full 72 hours with fent but how I felt then was already telling me that 25 mcg was too much for my body. I threw up at around 13:00 when I tried getting out of bed and eating something. Tried smoking a bowl since that helped with oxycodone related nausea but that didn't help either. Stayed in bed until 16:00 while sleeping and after that the nausea was gone and I could get out of bed again. After that I felt less ill, ate some dinner and that was the end of my transdermal fent story.
TLDR
Initially it was very fun! No regrets and I really enjoyed that saturday but I think 25 mcg was a bit too much and when steady state levels hit overnight, my body couldn't take it anymore. That sunday was pure hell though but I'm glad that shit humbled me. It reminded me that I shouldn't be fucking with this stuff and that fentanyl is too strong. I would definitely do it again if I had the chance but I would do 12 mcg or cut the 25 mcg in half and just smoke a lot of weed on it.
It is nothing like oxycodone though like you said, I do see the appeal but for me it induces too much sleepiness. Not the fun kinda sleepiness I have with benzo's but with this I just want to lay in bed and sleep all day.
I would not recommend this to anyone else tho, I love doing drugs and trying them since sobriety is boring to me and to those people I would recommend it to just try it and cross it off the list, but if you're not curious and not an avid drugs lover, then I wouldn't fuck with this. The feeling didn't even feel that recreative to me it was just very very sleepy.
Oxycodone stays the king for me currently. (havent done heroin or any IV opioid)