CA forms a chemical bond, meaning that it actually bonds to itself, which is why it works wonders on porous materials (ceramics, resins, wood, etc) and not so hot on plastics and metals. It has great pull strength, but very poor shear strength. It's hard to pull parts apart, but tap it from the sides and it comes right apart.
Glues like tenax, Tamiya (in the orange, hexagonal topped bottle) and testors (in the black bottle) form a mecahnical bond. They actually melt the styrene and then evaporate, leaving the two pieces of styrene as one solid pice. Impossible to break, you actually need to saw through it if you goof up. You can order these online at most hobby shops like megahobby.com, towerhobbies.com or ehobbies.com
-Fred