Isn't that the same as doing survival missions? Survival missions will also give you rewards every 5 minutes. Although they do get increasingly more difficult.
With the survival missions you always have to keep the life support running which means you are limited by how easy they are to get to. This way you only have to concentrate on killing things, you can take your time. I got 40+ Oxium this way last night and 8 or more fusion cores.