Wow.
I admit, I didn't spend a lot of time with RR on an emulator - I was waiting for an NTSC version to play on the real deal. Altirra or Atari800win with a modern USB gamepad is great if you don't have an XL, or to check something out quickly after downloading it, but I love hearing the SIO noise as the game loads from a floppy, and the look and feel of a composite monitor and a CX40. To me, it's much more impressive seeing something like this run on a 30 year old machine, than a PC.
Now that I've spent a few hours playing, I'm blown away. Sorry if I'm stating the obvious or what everyone already knows, but this game is phenomenal! Brilliantly done - responsive controls, elegant, detailed graphics, crisp sounds, and a nice ramp-up in the challenge factor. Love the dual action / puzzle theme that demands both quick reflexes and a sharp mind. Fun, fun, fun! I'm glad this came out on a weekend so I have time to devote to it.
I will definitely buy the cartridge when it's available.