Originally Posted by amanlikemike
There has been talk of this and it is technically possible, but we do not recommend it, due to the differing demands placed on pannier bags, compared to tail packs meaning that they need to be constructed entirely differently (e.g. heavy duty Cordura in place of flexible RipStop / Rhinotek; stiffened back panels; top opening roll closure and bolt-on fitment, rather than straps etc).
I wouldn't be at all surprised if a larger version of the Overlander 15 pannier bag (or an entirely new product along those lines) breaks cover at some point, but I don't have confirmation or info about it at this stage.
Sorry I can't be the bearer of better news.
I do see that it would be a whole new product, as it would have to be a top load, and not a side load - but it would be nice if something like that would come.... more flexibility