I distinctly like idea of a rack with an integrated locking mechanism for the trunk bag. You could get into the campsite, set up camp, and slide off the rear bags in about 10 seconds to store them in your tent. Then your bike can be ridden into town to check out the nearest cafe or restaurant without having all the equipment still lashed to it.
It SEEMS like a good idea in theory anyways, but has anyone here had any personal experience with it? How's the durability, quality, etc. I do notice the biggest rear bag Topeak makes that works with that thing is about 1220 cubic inches. I guess that's pretty wimpy as far as storage space goes, which means you'd have to run big front panniers as well for a supported cross-continent tour, and then you're losing out on the ease of removal aspect I'm so smitten by (Unless topeak makes a front rack I'm unaware of)