Megas is the titular mecha robot of Megas XLR cartoon.
Megas XLR stands for Mechanized Earth Guard Attack System, eXtra Large Robot.
Think of it as Gundam for the Americans.
Megas here is piloted by Coop, with Kiva and Jamie to defend the earth from Glorft and other dangers.
Just like the previous Evil Megas, this Megas is made by the same person : MarcGo26 from devianart.
The Evil Megas and this nice Megas doesn’t look that much different to me though. Probably I like Evil Megas more due to its color designs.