For a trip down to Cape Town I bought a new pair of Aerostich tank panniers -
Aerostich Tank Panniers - Saddlebags - Seat, Tank & Tail Bags - Packing it in :: Aerostich/RiderWearHouse Motorcycle Jackets, Suits, Clothing, & Gear
- in black.
They were excellent, very well made, and easily survived a year in Africa.
I have an Acerbis 22ltr tank and I had to fiddle a bit to get them to fit securely but it wasn't difficult. And they didn't budge once fitted.
Where are you?
I don't really need mine now. In fact, looking back, I think that having them in the first place just encouraged me to take too much stuff that I didn't really need - the Old Problem!
But they do put a good bit of weight forward and low down. I carried my complete tool kit in these plus some spares. (And oil lurking in the bottle of toilet cleaner strapped to the front of the right pannier).
If you're within reach of SE England you may like to buy them.
Here's a pic before departure:
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(I got rid of the tank bag pretty quickly!)
About half-way down, N. Kenya:
And at the finish line:
They're still in excellent condition although grubby with a year of dirt, dust and sand, and wear marks on the 'gripper pad' between pannier and tank.
Let me know if you're interested.
Cheers