ya know i am debating this as well
although hauling a 9 shot 590 around the field might be tiring
prolly weighs 6.5 -7 pounds
i am also considering the Benelli Nova
it seems a bit more field friendly
anyone shoot one with the 18 inch slug barrel?
http://www.benelliusa.com/special/novaslug.html
i think vangcomp can tell you about choking the 590 barrel
http://www.vangcomp.com/welcome.htm
mossberg calls it a cylinder bore
http://mossberg.com/pcatalog/lawprc.htm
whats the deal with the Double action 590DA?
none of the MSB chokes are listed as 590 friendly
http://mossberg.com/acatalog/pricestktube.htm
HTH
dZ