Bought this about 2 months back, and just now started trying to use it. A few problems.
First, it will not tilt precisely to 90 degrees, but stops slightly short, just enough so that my mill shows .002 slope every inch, so I guess its like 89.99 degrees. Just enough to cause problems. I will have to take it apart and do some filing/grinding.
Second bigger issue is that the bed is not completely flat under the jaws. Under the front jaw, the bed was ground into a slot for some reason, so the front parallel bar falls into this slot, making it useless. Even a relatively wide parallel causes issues. Either you have to live without that or stack up some additional bars behind the parallel you want to use. I wish I had noticed this before I bought it.
On the plus side, it seems really solid and seems to hold the parts well and is of course highly adjustable.
With some work, I can make it suitable, but these issues should have been solved at the factory.