disclaimer: I'm not a mastering engineer, I'm just some dude with a home studio, producing techno and have nothing better to do right now than to hang around on gearslutz.
I personally bought the A21-M without listening first. I could have sent them back if I didn't like them, but they are great so I kept them. It was a leap of faith, and I'm ok with that. Trying out monitors in my studio here in Iceland means I have to spend a ridiculous amount on shipping or have a very limited collection of brands to choose from.
PSI A21-M with the A225-M sub is really good. I don't believe they are better than SM9, but I don't think they are worse either. (but of course I haven't heard SM9, the icelandic store didn't have them in stock. they actually had a guy from focal bring a pair for show and tell (one time event) a few weeks before I went looking for them. but he took them back to france...

)
I believe when you have quality speakers you have to have a good room. I mean, if the speaker has +/-1db down to 40hz and your room has +/- 20db nulls and peaks, what good does it do?
And you have to learn how to use the monitor, so even if it does have EQ settings you have to listen to reference tracks anyway and learn their balance and how to use them. (I have to have a reference track when mixing in A21-M, else the balance goes out the window. perhaps it's related to how transparent they are, there isn't a lot of masking happening even if the bass is way too loud.)
once you get to used to them and learned their strength and weaknesses, the bottleneck probably isn't if you have SM9, A21-M or some other high quality monitor, or if it has EQ settings or not. It's more about you, your room and how much work you put in to the project. so in that sense I don't think it's absolutely crucial what brand of monitors you have as long as they are of high calibre, like the ones that are being discussed in this thread.
perhaps I'm stating the obvious but :
The proof is in the pudding. If you make great mixes on your monitors then it doesn't matter what you use (SM9 or A21). and both are certainly capable of helping you do that.
that said I'm still obsessed by reading about monitors and am constantly dreaming about trying out Quested, Unity Audio, ATC, Spiral Groove and others... keep it going