In the early 70's,i used to love the MXR90 and the EHX Small stone.MXR was classy and mellow (very transparent) and the EHX was thick and more pronounced (phasing).Recently,I bought a new EHX Small stone and was very disappointed.Nothing like the old ones.So,if you can find a good vintage MXR90 AND if you have tried it before and you're happy with the sound:go for it!I would say the same for a Small stone btw !Some time ago,i tried an old analog Ibanez multi-effect (just 4-5 pedals together) and the phasing was the best i have heard since the 70'sMXR and EHX.Most modern phasing have a lot of controls (multi-step etc.) but don't give you the "real" phasing sound.