I'd consider this if I had the option. Here in the US it's pretty well known that fetanyl is killing people and apparently it doesn't even require a lot.
If it can kill some habitual heroin user with a tolerance then I imagine it would easily do the same for someone like me who has no tolerance.
The issue that is or was killing people with fentanyl is that is stupidly hard to measure. 1mg is around the size of 1-2 grains of salt. So if you try measuring a dose that small, sometimes you get 2, sometimes you get 4, sometimes you get 6 maybe 8 pieces. When we dabbled in 2CB you could very easy go over the top from sharing a note. Important to give it a tap and clear any residue. Or use paper to avoid. 0.025 average dose. 0.03 is realms for bad trips.
That's a huge OD on fentanyl if you were to take x4 what a pill is advertised at. Especially for a habitual user.
I'd add also that fentanyl has now become hard to source. In the UK anyway. Due to a ban from DW sites due to the epidemic in America and media surrounding.