Why is there a cloth on the saddle?
For me, hard cases are so much more convenient that I hope to retire the soft bags.
Why? I'm interested.
There's a sheepskin on the saddle. Same sheepskin in the other pic on the other bike. Cooler when it's warm out with a little air flow down there. Seems warmer when it's cold out too although I can't tell you why. Less humidity inside my Gore-tex pants any time, but especially during or after a rain -- sitting on a wet vinyl seat doesn't let perspiration out but the wet sheepskin allows enough air through to keep my nethers dry.
My take on hard vs. soft bags: seriously wet weather requires either a rolled closure or zippers plus a plastic liner (or a rain cover which I've never tried). Any of those takes a bit more time to open and close than a latch or two. With liners (trash bags) you need to fold or roll the opening or somehow keep it dry. Fiddly time. The roll-top is better, but handling the roll itself gets hands good and wet. The buckles are not quite glove-friendly.
I've used worse -- a rolled-end waterproof bag with straps across the top. Trying to close it without loosening the straps means the contents can shift and the luggage is loose. The rolled-top bag in the CB photo at least eliminates that step.
Both tank bags have zippers and shed rain pretty well. (There's a different home-made tank bag on the other bike.) The openings are actually above the zippers so water going down or sideways doesn't get to the contents. They can get damp from below and both will get slightly damp if it rains long enough.
My favorite is the top case which has a single latch on the back. When I stop for lunch I can open, toss in the GPS, camera, gloves, close it and lock it in just seconds. Or a map change at a state line, open, get the plastic bag of maps (against the front wall) exchange, close, and latch.
Some people prefer top-opening side cases to make them as easy as my top case. My side cases and side bags have gear for camp plus "regular" clothes, i.e. not layers for warmth. Since I'm not opening them during the day the speed difference isn't really that important. I still prefer the 100% waterproof hard cases over the bags that I can make waterproof with a liner.
EDIT: And for around town -- hard cases all the way. I can use the tail bag I made, but the side bags are not as good for carrying partial loads. I really like taking a ride to the bank, library, hardware store, grocery, etc., and side cases are just very practical. Anything I buy at one store is secure when I'm in the next. The roads here make this kind of errand very entertaining instead of a traffic hassle.