The most used type of airsoft gun are AEG (Airsoft Electric Gun) these are powered by batteries and are more userfriendly comparing to Gas guns. They also need very little maintenance.
Maintenance for AEG is for the most part: cleaning the inner barrel & after a year putting some grease on the gears.
The types of replica's in the category AEG are: Assault rifles, Sub machine guns & Heavy machine guns.
Sportline: The Sportline replica's are buget based. These often have plastic bodies and lower quality gearboxes. The advantage is a lightweight replica with low costs!
Proline: The Proline replica's are the more expensive class. The most replica's you see, are Prolines. With a metal body, these replica's are more durable and will last longer. The gearboxes are often high quality. The advantages are that these replica's can take a beating and will last you a long time!