It might be worth looking at the Ventura rack which is simple to fit and even better, is easy to remove when you get home from a trip e.g. 5 mins.
It has number of configurations which can be fitted as well as a few selections of bags and rack fittings that can be chosen. One big advantage is that if you are travelling alone the bag can be reversed on the rack and sit on the pillion seat leaving the rear section of the rack available to carry other items such as a tent or another bag. This stuff is robust and well made by our Kiwi friends, I have tested it in extreme conditions and crashes.[You must be registered and logged in to see this link.]
You can also fit the H&B bags with the rack in place by simply buying 4 longer hi-tensile bolts from your local bolt supplier, both use the same mounting points on the frame and you don't need to drill holes for either.
These are older versions of the bags, the current Ventura bags are much more stylish.[You must be registered and logged in to see this image.]