If any tool make you uncomfortable, don't use it.
C2 is a plugin-orientated game engine,
When you insert object into C2 layout,
it's a PLUGIN.
Do you know that?
Sprite is a plugin, Tiledground is a plugin,
Browser is a plugin, Text is a plugin.
In very early version of C2,
Sprite animation editor sometimes cause crash,
Tiledground had its power-2 problem,
Browser functions can't be totally supported in mobile solutions,
Text slowed down the fps.
Ashley surveyed all the bug reports,
make the official plugins better and better, release by release.
Same as 3rd party plugin makers.
Sometimes they can't make a perfect plugin for you for free at once,
but most of them keep working with their tools.
No plugin maker, include Ashley,
can promise you any reliability of the plugins.
Even you are a pure official C2 user,
you may find the performance of your game can behave different on different browsers or devices.(e.g. WebGL effects, PC vs Mobile, Differnet resolution of PC)
So it's all about you trust or not, about you feel comfortable or not.
If you don't like them, just don't use them.
Or you can find what exactly happened inside your project,
ensure the real reason of the bugs.
If it's absolutely caused by any plugin,
tell the author of this plugin and send your testing capx to him/her,
I think most plugin makers are gladly to take your report,
and make the plugin more and more reliable.
Maybe it's a better way than questioning the reliability of plugins before you clearing the cause of the bug.