For the longest time, I didn't understand the invective heaped upon my poor BT200. I believe I may have figured out the reason behind the bias, unjustified as it may be.
In setting up a recently acquired GXP-2000 (I love my friends! They keep an eye out for this stuff!), I noticed that the volume continually cycled up and down, repeating every 3-5 seconds.
The problem was both extremely annoying and very easy to fix (firmware upgrade!). I can imagine that someone without the knowledge and/or resources to acquire the new firmware might become frustrated with the phone's issues. However, those issues aren't permanent and neither should the bias against the phone.
Alternative attitude: most of my Grandstream's were given to me (they were free), so bite me! (heh)