I have th Krauser tail rack with the panniers mounted. I have replaced the Krauser bags for a set of Givi E41 mounted on universal plates. I also mounted another universal plate on the the tail rack and have put an E52 top case (with brake lights) on it. I had to reinforce the tail rack with two pieces of steel tubing to make a triangle. The rack alone is not stong enough to support the E52 (or the E46 before it). My weight distribution problem is solved by a Luftmeister fairing on the front. That keeps it balanced out. I'll get some pics. Two keep the turn signals with the larger E41 panniers, I moved the turnsignal bar aft to the bottom of the tailrack universal plate. The turn signals are connected with SAE quick connectors so its easy to take apart if needed.
If I was just going to have a top box then I would get the Reynolds and have a Givi universal plate and a Givi E46 or E52 (with Brake light - can't have too many brake lights!) The Reynolds Racks come up on ebay or the IBMWR market place every now and then.
Here is a picture:
TTFN,
