I bought both Megaton Rainfall and No Heroes Allowed! VR. Here's some quick impressions of both:
Megaton Rainfall
It's a pretty simple concept yet playing it does make me smile. There is a serious rush and satisfaction of flying at mach speed while zipping around blowing stuff up. Flying into space or taking a moment to land in a remote field is cool; granted, everything is simplistic looking aside from a few landmarks here and there. Just think of the gameplay as a shooter with 360 degrees of movement. The controls are intuitive after only five minutes of play. I disabled all of the comfort controls and had zero issues. It's rather astonishing as I would expect this game to be a vomit inducer considering you're whizzing around at crazy speed and stopping on a dime without a cockpit and yet it's remarkably comfortable. The story stuff is meh and you are usually just waiting for those cut-scenes to end so you can get back into the action. There are a few glitches every once and a while but nothing deal-breaking. It's a great game when you want to kill some time and just feel like a god. Shooting enemies is genuinely fun (and there is a satisfactory amount of variety) and the sense of scale is impressive, especially with the enemies. The sounds design is also fantastic.
No Heroes Allowed! VR
This game is very charming! The graphics are gorgeous (not a single jagged edge to be found), the characters are fun and voiced with charmisma, and the music is perfect. The gameplay is essentially a mix of tower defense and RTS where you breed monsters to defeat the heroes and ultimately take their castle. There appear to be around 15 levels. There is a lengthy tutorial and the gameplay mechanics are more complex than I was expecting (but in a good way and not confusing). I only played one level so far and it's fun. It could be argued that this is a game that "doesn't need to be in VR" because it's essentially a table-top game (you literally look down at the table in front of you) but I think it uses VR well to make that miniature world come to life and all of the commentary from Badman and Badmella as they watch along side you adds a lot to the experience. I'm not really a fan of RTS or tower defense games yet I was enjoying it none-the-less. This game is very polished and that's not surprising as it was made by Sony's Japan Studio who also made Playroom VR. This game shares a lot in common with Playroom VR: its aesthetics, graphic fidelity, and charming characters. Your DS4 is even part of the game and used in much the same way as in Playroom VR.