MXR vs. E~H hmm
I have two smallstones, I like them very much and I've never had one problem with E~H. I don't like phase 90s at all, at least the new ones. But, there aren't any E~H pedals in my main setup right now, but there are 4 by MXR - Dunlop/MXR - Dunlop. My phase of choice is a old script phase 45 that I’ve had for ever, and it’s a cool pedal with a great sound but it has it's quarks, like it eats batteries and it has a little tone suck, but I have in my loop'w'blend so that is no problem.
I think you are really going to just try a few out to see what you like. If I was to buy a new phase I'd look at the E~H nano smallstone or the MXR phase 100.
I have kind of changed my mind on some of this lately. After retrying a phase 90, I don't dislike it as much as I did before, I still find them a bit cold but still pretty good, I've also pretty much given up on using smallstones for "normal" phase usage, I find in less I use it with distortion the smallstone is either too subtle or kind'a muddy; maybe if I didn't use flats and a sound centered so much around low mids and lows I could get more use out of the SS. So, it looks like I'm sticking with my MXR 45, which is the first pedal I ever got. I think if I was to buy a new phase I get the Tone Factor Nebula Phase, it's based on the 45 which as I said is my favorite phaes sound.