Hi Brian
I would want to know what the inside of the vice between the jaws is.
Some of these cheap vices have a rough casting between the jaws or a bit of a rough gap so you can't put a parallel in it.
Also, the base loses you headroom but if you remove it, you can only use the vice at 90 degrees to the X axis.
That would be fine for most of the time but 10% of the time you may need the vice in line with the X axis and unless your Tee slots are the right distance apart you may not be able to clamp it down.
regards David