I have that rack and like it as well. I got it specifically to use with my other Topeak accessories: a trunk bag and a basket. I've used it with panniers and with other, random items strapped to the top, but the draw for me was the easy-on/easy-off Topeak system. If I was going to be swapping carrying solutions between two bikes on a regular basis, I'd definitely want two compatible Topeak racks with the corresponding bag because swapping the bag between bikes would be extremely simple. But a trunk bag is not panniers, and, although the sides fold out for extra pannier storage, I only use those occasionally. If I was going to use the fold out panniers daily, then I would probably just use "real" panniers. As it is, my commute load has outgrown my current trunk, and I find myself using a satchel and a basket. But the plan is to upgrade to the largest trunk bag with fold-out panniers in the future. There is also a matching rain cover, but I can't speak to its effectiveness.