Let's weigh out some pros and cons of each- Guardians get a massive Arsenal and can equip any weapons they find at anytime and carry excesses of ammo for their personal weapons. Spartans have a much smaller Arsenal and have to find ammo for their weapons on the battlefield. And they can only own 2 weapons at a time. The rest they have to find while in action. Guardians Can summon a personal vehicle, but the sparrow doesn't have any weapons and is very fragile. They can however drive enemy pikes and interceptors if they find any. Spartans don't have a personal vehicle, but allies are constantly dropping down powerful vehicles and artillery that they can all pilot. And they can pilot any enemy vehicle they capture, including tanks. Guardians have the ghost, a door opener that essentially makes them immortal and invulnerable to everything that doesn't contain Light, with the exception of fall damage. So dying means pretty much nothing to them. They can be killed however, if they are found in a darkness zone and their entire fireteam is dead, they are dead. Forever. Spartans aren't as fortunate. If a spartan dies, they are MIA. So basically no revives for Spartans. They go YOLO. Guardians have small fire teams. Most guardian missions are for 3 people or less, most going solo. But for Raids, they can go in with a maximum of 6 people. And they have very little communication to the authority. Usually there are less than 2 people overseeing them, not including the ghost. And there are no human allies, so it's guardians only. Spartan teams are much larger. There is a maximum of 16-20 Spartans in one team. They also often work with ground soldiers as allies. And they have a great communication with AI and authorities such as UNSC and Cortana. Guardians training extends past their birth. They have the crucible, a place where they can hone their combat skills against other guardians without the danger of being killed. Spartans get most of their training before becoming Spartans. Because there is no multiplayer training since Spartans go YOLO so they only get to hone their skills by killing stuff on the field at the danger of dying. So, which would you rather be?