Having sailed on the Chesapeake for the past 18 or so years I would say that none of the three are ideal for the Chesapeake but that of the three only the Irwin makes any sense at all. The Chesapeake is a predominantly light to moderate sailing venue. It puts a premium on light weight boats that can beat and run well. The predominant winds run up and down the Bay. It also puts a premium on boats that are good in a chop.
The Columbia 8.7 was a very mediocre design in my opinion. This was part of Columbia''s "Wide Body" series. That whole series were not very good boats from a sailing ability standpoint and were particularly poor in a chop.
The Vancouver 27 has very much become a cult boat with a strong following for distance cruisers and wannabe distance cruisers. They are charismatic little boats but are miserable in the kind of light air and chop that is so dominant on the Bay. I am afraid that like so many heavy cruisers, the Vancouver would end up being a trawler with a steadying sail rather than a sailboat more often than you might like.
There were quite a few Irwin 30 models. The early Irwin 30s were pretty fair sailors for their day. They were centerboarders with shallow draft which is nice if you are into gunkholing. Later versions included some nice sailing competition models and some strange cruiser/racer models as well. Irwins are not the best light air boats but are certainly better than the other two. Irwins had a reputation for being rather poorly built but I think that varied from model to model. Still they had a reputation that fell somewhere at (and sometimes below) the Hunters of thier era and that, at the very least, can affect resale. (Other choices of this ilk might include Catalina 30''s, Oday 30''s, Ranger 28''s and 30''s, Newport 30''s and Hunter 30''s)
One great thing about the Chesapeake Bay is that its seems like somewhere on the Bay you cna find an example of almost every type of boat that has been built in modern times. Over the course of the year, the used boat market is quite broad and you should be able to find just the right boat for your needs and budget.
Good luck
Jeff