I was faced with a similar problem late last year. I got the 1 1/2 hp
Woodtek system from Woodworkers Supply and have been very happy with
it. They now provide 1 micron bags as part of the original purchase.
I don't believe anyone who says they catch 100% of the dust, but I'm
definitely catching at least 90% on all tools and my coughing and
asthma symptoms have stopped. I also got the small build-it-yourself
air cleaner from Penn State ($115) -- the proof here is on the filter.
You'll need to build or buy appropriate hoods for each machine. I
sealed the bottom of my contractor's tablesaw with plywood and an
integrated dust hood. Built hoods from plywood or masonite for my
chop saw, planer, router, bandsaw and drill press. Will be making a
downdraft table body soon (haven't been doing much sanding the past
few months, but the time rapidly approaches).
With time, I obtained metal ducting cheap and added gates for each
machine (these can also be built easily). The tablesaw, planer,
jointer and bandsaw are on mobil bases and all share one duct
Be sure you have adequate wiring for your needs.