Dissos are used from some people as potentiator or tolerance reduction or anyway achieving a different effects.
Eto analogues are all dangerous, maybe only Butonitazene could be considered relatively safe with his 20x potency - but seems the RoA with decent BA is only smoking it on glass pipe but the taste will be shitty, certainly not the sweet and mild taste of fentas analogue, where your body/mind/soul were happy in less than 30 seconds. Generally all Eto analogues are kicking it with some delay, and the long-legs one are dangerous because even if effects is gone your redose, you risk to pass out without expecting it.
Etazene is the only only one short acting and with decent euphoria, but only the first few times, then it's like all other eto anallogues..you just take it "because", killing tolerance, and eventually falling to sleep or passing out after a certain amount. I'm done with eto analogues, I work on reducing my tolerance as much as I can to enjoy other upcoming RCs of other classes instead, and I've a golden rule I do not use ANY opioid > 10x (even if diluted) for daily maintenance. Everything stronger no matter the willpower, they just take control of me, and - if they were f- analogues I'd at least have amazing times, but to just have crappy effets of insanely strong opioid but with poor receptors affinity and only a strong analgesic potency, fucking up the tolerance..then no thanks, i'll pass.