Ripoff of a ripoff.
Interesting, nobody seems to have noticed that this was a ripoff of the Magnificent Seven, which was itself a ripoff of Akira Kurosawa's Seven Samurai. Robert Vaughan plays the same role in BBS & MS.
It's saved from being crap by the goofball take on everything. For instance, Nell, the talking spaceship, is modelled on the Winged Victory of Samothrace. The brilliant and eccentric scientist naturally has a beautiful daughter, who naturally warms to the hero.
Bizarrely, I remember more about this picture than about the (overrated) Magnificent Seven, and remember it much more fondly.
Thank you Roger Corman, I give it a ten.