I have not tried a Sig, but i have found my XD45 full size to be very simple and almost instinctively operated and serviced. A friend has the XD9 and has been similarly satisfied with it. He chose the XD9 rather than the XDm9 due to the discount on the XD and his perception of the differences as not very significant.
Dead Bears, the only good kind.
GANDER MOUNTAIN OF HATTIESBURG, MS IS OVERPRICED, HAS LOUSY CUSTOMER SERVICE, & SELLS BEAT UP PISTOLS TO LITTLE OLD LADIES AS "NEW". :p