Rob_E

+1

I see you've ordered the Topeak stuff. I have a Topeak rack and bag, and I love it it. I don't think you'll regret the purchase. I also have the rack-compatible basket as well as the collapsible milk-crate-style container with roller wheels and handle. I rarely use that last one, but it is a clever piece of gear. That said, I never use that stuff when touring, other than the rack itself. The Topeak bag is solid, but heavier than a lot of other gear and with less overall capacity. For what you're carrying, I think it will do the job fine. For a first stab at touring, it's a decent bag. For commuting, I think it's a great bag. I can fit a change of clothes and lunch in the main compartment, and if I have to stop at the grocery store on the way home, I can fold out the panniers. I have had zipper and seam failures in the past, particularly on the fold-out panniers. I like them fine for occasional, I-didn't-expect-to-be-carrying-this-much-stuff-today use. If I know I will need the extra capacity, though, I will usually just bring my panniers. I eventually upgraded my Topeak rack to the model with a 2nd, lower rail (DX model, I think), so that I can use my regular panniers alongside one my Topeak accessories.

For touring, including credit card touring, I am fine with panniers, and if I have my rack on the bike, I'm probably going to use panniers in some capacity. I like Ortliebs. Waterproof, solid attachment points, and, unlike some folks, I consider the lack of compartments to be a feature. I don't have to select what gear gets stored where based on compartment size. It's one compartment, so it either fits or it doesn't. Need to keep some items separate? Put them in their own bag in the larger compartment. Also, since I usually have two panniers, it's actually two compartments. For the trip you are talking about, one would be fine. Even when camping, I've moved to the smaller, front-roller or sports roller or whatever-they're-calling-them-today panniers that I put on my rear rack.

For a rackless set-up, I've been happy with Revelate Designs gear. https://www.revelatedesigns.com/ For credit card touring, I can fit most of what I need into the Saltyroll. For trips that need more gear, a frame bag and/or one of their seat-bags work well. But I've never need them when credit card touring. I did the GAP and the Katy Trail with most of my gear in my Saltyroll bag.

Speaking of, both the GAP and Katy are longish, off-road, rail-trails with plenty of places to stop for the night along the way. Doesn't mean the trail you're planning should be dismissed. It's one I've been wanting to ride as well. Maybe it won't be super interesting, like Papa Tom says. But it will be an experience. And if you're worried it won't be scenic enough, definitely seek out the opinions of someone who's actually ridden the trail. All of the trails I've ridden have had their less-than-stellar sections, and even the parts that start out scenic can get monotonous without variety, but there have also been some standout sections that made it worthwhile. And part of the fun is experiencing it first hand. Not every trip I've taken is worth repeating, but there are none of them that I wish I hadn't done.

Papa Tom

To the OP: I forgot to tell you...Now that you've made the investment and ordered the Topeak bags, people are going to come out of the woodwork to make sure you doubt yourself and have buyer's remorse before they even arrive.

You made a good choice. Be gentle with the zippers (NOTHING is made like it used to be made) and move on to planning your ride and creating an awesome memory. None of this gear sh-t really matters in the end..