I picked up some cheap trains last year off Aliexpress they same time I got some lamp posts. They are roughly 6mm scale (with the scale on each box) and at first glance pretty good. They cost me $10US for 9 trains and I got them from here
I was going to write a more detailed review but I have been away for 1 1/2 weeks and will be away again soon, so I will write that after I get back (along with a backlog of blog posts).
Here’s some quick snaps of the boxes and a few models. I think they will need a repainted and some joins filled, but does depend on how well they assemble. At the very least, some washes and weathering will go a long way.
Here are all the boxes- certainly there is a good mix of train types and names!
And two of the unassembled models and there is more photos on the Aliexpress page