Theta:
Within the realm of 4-substituted tryptamines, they're actually decently different, but because they are in that same realm they do still have a number of similarities too. Their durations are similar but differ slightly, and a lot of people seem to think that 4-HO-EPT is notably shorter-lasting than most 4-substituted tryptamines. They have a similar side effect profile, which is to say there aren't many, but things like nausea, dizziness, and increased muscle tension leading to shakes can occur. The trips also follow a similar time course to mushrooms where within the first half hour to hour and a half they really develop in an introspective and somewhat physically heavier way but the effect lightens up and allows for more direct stimulation and extroverted behavior as time goes by.
The hallucinogenic styles of 4-HO-DET and 4-HO-EPT can differ significantly from mushrooms as well as 4-HO-MET, 4-HO-MPT, 4-HO-MiPT, and others that contain a methyl group on their tail in particular, but again still have recognizable elements. I personally find 4-HO-DET to be a heavily hallucinogenic substance, while the hallucinations of 4-HO-EPT I find to be subtler, but everyone's reaction is different. While they do differ, the hallucinations of 4-HO-DET remind me more so of mushrooms in style and organization, but the geometry has different color schemes and the visions show different kinds of people in different locations with different emotional vibes, which tend to feel much more down to earth and potentially strange than those of mushrooms; on the other hand, the hallucinations of 4-HO-EPT remind me more of 4-HO-MET, 4-HO-MPT, 4-HO-MiPT, and also LSD, though for me is subtler than all of these and has a unique color scheme from all of them, but a closer visionary thematic style to them than 4-HO-DET has to mushrooms. 4-HO-DET I find to be stimulating in a way that makes me want to seek out pleasure, it has some sexual properties that remind me of those that the DiPTs are best known for, whereas 4-HO-EPT I find to be more orgasmic on its own and makes me content to roll around in bed enjoying the pleasure of it.
Those are pretty much the thoughts about them all that come to mind, I hope they help.
