4-aco-dmt is indeed active with the IV ROA, and is exceedingly powerful. I've done it only once, at 35 mg, and it was explosively potent!
I have plenty of experience with this stuff orally in the past, and have gone up to 50 mg orally. The IV dose I used was definitely the most powerful experience I've had with it.
At 35 mg it was instantaneously overwhelming, and I would classify my experience as some type of breakthrough. It was the type of trip that gave me a fear of death again, and renewed my appreciation for life. It was amazing, but I don't think I was quite ready for it.
If I could go back and do it again, I would start MUCH lower. Probably 10 mg would be enough for a solid experience without completely going over the edge.