Originally Posted by
Carbonfiberboy
Besides the terrific durability and stability, the thing I like most about my SS Tubus is the SS. It looks perfect all the time. Two positives about rear rack only: lighter weight and less wind resistance. Both are very noticeable. As far as handling goes, try carrying less weight. Not too hard to get the whole load down to 20, including rack and panniers.
Rear rack only also adds somewhat to visibility. Nothing like a large hind end to get someone's attention. (I think there's a rap song about that, but I would likely get banned if I linked to the video.)
However, in the case of the OP, the downsides of rear-only likely outweigh the upsides. He will have to mount his panniers very far aft to clear his heels, especially if he wears anything with a heel cushion to ride in (I wear size 15, so I have a bit of experience with heel clearance issues). That behind-the-axle loading will seriously destabilize the bike, especially going up or down hills.
Maybe the best solution is one of the rack top bags recommended by Tourist in MSN with the idea that capacity can be added with low-riders in the future.