This movie is your classic "go to another planet and find monsters" film. No more, no less. Although the atmosphere was generally a little bleary and low-key for my tastes, I liked it. The alien monsters were savage and prehistoric, but didn't conform to traditional dinosaurs so much that they didn't look alien. The haunting music/voice could have been played up a little more, but maybe it's best that it was left with a tantalizingly mysterious ending.

This movie delivered what I expected of it, no more, no less. The monsters were decent in quantity and quality, the pterosaur sculpture intriguing, and the unearthly singing voice was quite interesting. I wish the plot had allowed for more exploration of that, and I wonder what part those things played in the original russian film.

Most of the scenes of this film are from a movie called Planeta Burr, a Russian film purchased by Roger Corman for a few rubles. The scenes with Basil are spliced in and the original Russian script re-written to make the action fit a new plot line. The original Russian version (which cannot be found anywhere) involves only two groups of Cosmonauts exploring Venus searching for Marza.
The same scenes are incorporated into "Voyage To The Planet of Prehistoric Women" wherein the name of Marza becomes the name of Earth based mission control.