No flip-flopping here.
I’ve been a user of both, for different purposes, since they were first, respectively, released.
They’re really only “comparable” at the most superficial level. And that’s a simple use case that involves playing from a single source, to a single destination, for a single user. If that’s how someone intends to use Roon, then it’s missing 95% of what Roon does.
Audirvana (3.5 or Studio) can only do two things that Roon can’t. The first is host plug-ins. There are easy ways around this for local playback. The second is stream to DLNA/UPnP endpoints. None of which need Audirvana in the first place, it just happens to be convenient if you don’t want to setup your own DLNA/UPnP server first (which is trivial to do).
Audirvana’s benefit was that it was a one-time $79 perpetual license that allowed use on two machines, where Roon was $100/year (or $500 lifetime, later $700 lifetime) which allowed a single core (server), but as many users, controllers and end-points as you want - all of which could play independently or in sync.
You can have all your Roon users streaming different things to different devices, all using different EQ, DSP, and other settings, all at once, on one license, simultaneously. If you want to do that with Audirvana Studio then it’s one license PER simultaneous user, still can’t do proper distributed audio, still has issues with it’s network replay that have been around since 3.5, and winds up costing more than Roon!
Since Studio spells the end of development for 3.5, with many issues long-since left unresolved, it’s basically a dead-end product. I decided I’d rather spend $100 a year on another Roon license (my main license is a lifetime one from the first month it was available) for my laptop (which can’t see my core when I travel, and I didn’t want to deal with switching core licenses around) … which works … and is FAR more functional … than spending $70 a year on Audirvana Studio (especially in its current state).