Now you're talking. The yellow Walmart piece might actually get the nod! My current bag is getting a little worse for wear.
Oh and about that rain - during the fabled SW monsoon (July and August, and tends to coincide with Summer trips), it's not uncommon to dodge rain every single day. Heavy rain.
Who knew? It never rained like that in SoCA.
One other point about my dry bag, as I said it keeps it's shape even empty. Empty or crammed full, it's almost the same size.
I run my duffel sideways on a solo rack on my rear fender (no back seat or luggage rack; supervalk IS), and my soft duffels sagged right down and laid on the bag lids and rubbed the paint pretty badly on my first long ride. Even with a soft leather duffel. So I cut an appx. 18" 5/8 dowell, zip tie it across the solo bar, and bungee the soft duffel across it, to hold the ends off the saddlebags/paint (and that works). Also, during the trip, it is a PITA to get into either saddlebag with the soft duffel bungied down tight over the lids. And, if it rained, I had to stop and pull it off and bag it with the leaf bag and put it back on.
After getting to the motel and taking the bag inside, I had to take the dowel off because I got tired of being asked WTF is
that for? (A wooden radio antenna.)
So the major reason I spent larger than necessary for that particular dry bag is that it needs no support to stay straight, even loaded heavy, and I can get into either saddlebag easily when it's tied on. I use a big net bungee over the whole dry bag (highly recommended), then a single bungee on each end.
It also has a little reflective piping like bike jackets.
I wanted the white accent one for visibility (while traveling), but they were out.
The funny thing is that for all the right reasons it works on my supervalk, it does not work on my trunked interstate. It's too big to go in the trunk, and on the backseat (must be on end), the trunk will not open at all unless you pull it off. And I won't carry a big bag like that fully loaded on the trunk rack. So a soft duffel (or tall kitchen bags) goes in the trunk (which is OK).