This recommendation seems like it makes no sense, but there is logic behind it. If you're one of the people who really enjoyed Gunbuster's high-school/boot-camp arc, and for reasons other than the bath scene, then you'd probably enjoy Starship Troopers.
It dedicates a good 5 episodes to Johnny Rico's training in power armour piloting, and plays out remarkably close to the book.
Both are similar but also very different. Uchuu no Senshi revolves more around the bug killing where as Gunparade March focuses heavily on the relationships of the characters and less on the bug killing.
Both are about humans vs bugs. Starship troopers (aka. Uchu no Senshi) is about the earth being attacked by an unknown bug life form located somewhere out in the vast space galaxy. Blue Gender is about the earth being over run by over sized killer bugs and humanity fighting to maintain whats left of their own existence from being wiped out.