I've been comparing the official Minecraft RTX, with the PTGI mod currently in development by @sonic_ether, and PTGI destroys RTX in nearly every way which is so strange to say. With few exceptions, nearly everything in the PTGI mod is more appealing and natural to me.

The BIGGEST example is water. Hopefully nvidia can fix this, but currently water in the RTX build looks bad imo. These screen shots are different worlds and slightly different lighting conditions, but you get the idea.

Left = RTX

Right = PTGI mod for Java Edition

No matter what lighting or weather, the PTGI water looks 1000x better. Has actual water caustics which by design improves the way lighting interacts with it, plus reflections look more natural and sharp vs the blurry af ones in RTX which make the water look like glass.

Same applies to being underwater. In the RTX version (left image) everything looks washed out with HEAVY god rays in direct sun, or just a sickly green in any other light. Compared to PTGI (right) with a more realistic look and FANTASTIC shimmer effect.

Not trying to knock on the devs behind the RTX version, there are good elements to it, and it is still in beta so things can change, but in its current state PTGI leaps all over it. Which is IMPRESSIVE considering it is one guy working on it and is running in software.

Some more screenshots for your viewing pleasure.
2 RTX pics and 2 PTGI pics.

Don't want to make this thread too long, but I also have to mention the god rays in the RTX version. They're WAY too strong and annoying. PTGI uses them in a more subtle and natural way that's easier on the eyes and doesn't wash out the image.

Left = RTX

Right = PTGI