As Mill stated, they suit your needs.
They get dissed so much because some new players want to use those Wal-Mart guns into organized big events, where everyone has a high end AEG. To say the least, those people would get smoked.
IE - If you showed up to a place with a twig, to play pool and everyone had good quality cue sticks.
Imagine how that'd go?
Your twig would probably snap and such, it would just be a mess and waste of time. Let alone you'd probably get made fun of hahaha