If you could only have one of these which would it be.

Context: I have a minibrute 2s and am buying a rackbrute 6u next week and my first ever two modules.
One will be plaits the other will be a reverb/delay.
After hours and hours on YouTube and modular grid I have these three on my final short list. (Although I really liked the qu-bit prism too)
I know the practical thing would be to get a multi-fx like the Erica Synth Dual or the FX Aid XL but I am totally going for fun over practicality.
Which one would you choose?

I've always liked the Mimeophon, but Desmodus is unique too (and you can change firmware on DV).

Depends, if you already have similar modules like Plaits or Rings and don't have the Mimeophon or Desmodus then go for the effect module. Picking between Mimeophon and Desmodus is more difficult which is why I ended up getting both. Mimeophon can do more but Desmodus is way easier to use as a beginner to modular. All three are great modules! I have Plaits, Rings, Mimeophon and Desmodus and now I really want Beads aka Clouds v2 so that I can feed it into Rings for the old muff wiggler meme.

i have a dv and like it a lot, but it can only sort of be a delay at the lowest density setting. it’s mainly good for big washy tails and feedback. the sidechain is a nice touch. i use it on the distortion setting much of the time, and shimmer can be nice as well. it can be reflashed into a proper delay (Imitor Versio). i haven’t tried it but read mixed reviews - too many delay taps seems to be the consensus but of course that is personal taste.

personally i would love to have a mimeophon and think they would go well together. forced to pick one, i might go with the mimeophon just since it seems like it can do more overall. bigger and more expensive though, which is always the dilemma :)

Haven't used the other two, but I struggle not to use my mimeophon in any rack it's been in, it just sounds so good.

I haven't used Beads or Desmodus, but I do have the Mimeophon, and I totally love it. As a noob I had no problem coming to terms with how it works. It can do straight delay effects or go totally off the wall. I originally bought the Erica Black DSP multi effects but sent it back to get the Mimeophon.

I have Beads and Mimeophon, no experience with DV. Anyway, they're very different modules. If I had to go for one, I'd say Beads, but it'd be better to make room for both :)