Sobor

I find that the watershed for me with algorithmic reverb is in the early reflections, especially the way those blend with the dry transients, and the way they transition into the tail. There are a lot of good options out there if you're looking for somewhat sparser/less diffuse early reflections. Valhalla Room and Vintage do this really well. Supermassive does that exceedingly well too, if you're not attached to a specific classic sound. Many others do too. That makes such reverbs a difficult sell nowadays, since there's such good options available for cheap or free.

If you're looking for dense and smoothly diffused early reflections, which blend well with the dry sound, things get a little trickier though. I have yet to find a free or cheap option that does this well, though admittedly I've not tried everything out there. That being said: IMO Sobor is one of the best options out there right now if you're looking for those smooth ER's. Of the ones I've tried the only one that does this better is FF Pro-R, which is more than double the price. The new Baby Audio thing does a pretty good job at this too I'd say, though I found it a little splashier than Sobor.

That smooth early characteristic is what makes or breaks "natural" sound in an algorithmic reverb IMO. And while Sobor is somewhat CPU-heavy, that could be weighed against the fact that one might otherwise reach for a convolution reverb for those realistic duties, which could easily cost even more cycles.

I'm very impressed. If this had the on-board frequency shaping of Pro-R I might consider them equally valuable, making this a better deal by far.