You can always give Marco a call at LightObject and see what he thinks. He travels to China quite a bit and knows the machines that are good and the ones without any support and he has invested quite a bit of time over the past 2 years getting laser parts for his site. He sells a pretty good looking laser machine but I don't know what it is like as I haven't seen it used. He knows the good companies and the bad ones.
I have bought the DSP from him and find it to be a very worthwhile bit of kit - for my machine anyway which is home built. I can push the laser head to 700+mm/sec but find that the extra room it needs to get the head up to speed is a bit of a waste of time and 500mm/sec to 550mm/sec seem to be pretty good speeds for me.
You could also buy a Zing from Epilogue as that is their budget laser.
I am not completely useless.......I can always serve as a BAD example.