What exactly is so bad about them, then?
Well, you get what you pay for, so for the price I guess they're okay.
That said, if you want good tone, avoid them. Even BOSS pedals sound better.
If you want pedals that don't swallow bundles of signal, avoid them.
If you want pedals that can actually withstand normal use without breaking like the plastic turds they are, avoid also.
And to add insult to injury, they buzz and hiss like crazy when you're not playing.
Moral is: DO NOT buy behringer pedals, ever.