Sheila, DH has 2 bags like the link you posted; he bought them many years ago and used them for his Trek 5500 and the Kuota for when we did long rides or for commuting. He tried it on my bike, but my bike is just too small for it. They are gorgeous bags, though, which is why he has kept them. I don't know what brand they are, but they look exactly the same.
I axed the idea of using my pannier, too. I absolutely hated it, though I used it for a long time on both my Jamis Coda and my Guru. However, both my new Topeak trunk bag and my Arkel bag don't change the handling of the bike at all, the way a pannier does. It just feels incredibly heavy. The thing is, I can take the Topeak bag off in a second, for rides when I don't need to carry stuff. Like tomorrow, we are taking our granddaughter in the Burley, on the bike trail. I can put my stuff in the trailer trunk.
I didn't ride to the gym, although it is absolutely gorgeous out, was 56 at 5:30 am. My legs were toast when I got up, from that little 9 miles I did yesterday on my commute. It's fine now, and I suspect riding the Ariel with the packed bag is going to make me feel like my Silque is just flying. I will find out on Sunday.