IMHO, dust collection is not that good of a sole criteria to select a table
saw, or to replace one, especially if its a vintage Unisaw. I am not that
familiar with the older Unisaws, and they might not be dust friendly, but
can it be retrofitted with a sloped floor, cover etc.?

The main products I want from a table saw are precision, reliability, safety
and things like that. Beyond that I'll try to make dust collection work.
Don't get me wrong. I do believe that dust collection is an important
factor but I don't think it overrides the craft, itself.