Next spring I'll be traveling in France for 3 weeks and then doing a Rick Steves Tour. Unlike on previous trips, I don't think a carry on bag will be big enough. In the first part of the trip, we'll be doing some train travel, so I don't want a giant or heavy suitcase. Does anyone have suggestions for a relatively lightweight relatively small checked bag? Also, we don't like the clamshell design of the Away medium checked suitcase (otherwise the size of that big is good). We find it hard to use the clamshell in a European hotel room. Thanks!!
I'm happy with my current bag. I also hate clamshells, and it weights less than the Away. 
It a 2-wheel, though, which is my preference.
https://eaglecreek.com/products/gear-warrior-xe-27-luggage
I've used a RS convertible suitcase/backpack for several trips to Great Britain, Belgium, and Italy, for up to 6 weeks at a time. I think there's a newer version available now, as mine is about 8 years old but it's still going strong despite heavy use (and tough handling by airlines, I'm sure). It's very light and I have used it both as a carryon and as a checked bag. I especially appreciate being able to use it as a backpack - I'm 69 now and it's easier to carry it that way than as a suitcase.
I loved my lightweight, not inexpensive bag. ( has a five-year warranty) that I carried to Germany last year. I did a lot of editing to get the weight down. I put in the Lufthansa box by the gate to make sure it fit just for reference.Here are the details. https://community.ricksteves.com/travel-forum/packing/packing-report-for-sunny-skies-6-nights-in-germany.
If you like the Away medium, then you are looking for a 26" bag.
My first suggestion is if you live near a store like TJ Maxx, Marshalls or Ross, head over to them with a measuirng tape and a luggage scale. They usually have a decent selection of checked bags on hand.
Next, look to see if Samsonite has a store anywhere near you or any major luggage store at all. If so, go check out what's available.
Of course, your selection of online bags is extensive but make sure the return policy is good in case you don't like the bag.
One last thing...you say you don't think a carry on size bag will be big enough. Do you mind me asking why you think that? Are you attending anything where you will need special clothing? If not, why not just pack the way you did in the past and do laundry a bit more often?
You might have a look at TravelPro luggage, as they have a fairly wide selection of products. The soft-sided luggage doesn't have a clamshell design so that should fit your criteria. Some of their carry-on models are a bit larger so may have enough capacity.
Well, there are lots of brands available in the market which you can but online and offline as well. I personally recommend you go with American Tourister Airconic 2.0 Medium Check‑In which is of medium size and is very light weight with best quality material.
For. our long trips of 6 to 8 weeks, we found a carry-on was no longer feasible what with hiking sticks, prescriptions, and clothing options that cover us from warm summer temps to cold mid-fall temps. We bought Osprey rolling duffles much like this one https://www.luggageonline.com/products/osprey-packs-rolling-transporter-60l?variant=41160827273407&country=US¤cy=USD&utm_medium=product_sync&utm_source=google&utm_content=sag_organic&utm_campaign=sag_organic&gad_source=4&gad_campaignid=22329265861&gclid=Cj0KCQjwvJHIBhCgARIsAEQnWlBT_cG3g1J_9LzMrCXhrLvfrAvVia9heDktfK8k0UJ82vS3Zee7sS0aAltoEALw_wcB and have used them now for a half-dozen overseas trips where train travel is the norm. They are cavernous and flexible to pack. Not cheap, but occasionally you can find them on a clearance site. I am such a fan I would not hesitate to pay $300 for a replacement.
I use Osprey packing cubes like these https://www.osprey.com/ultralight-packing-cube-set-ulpackcbsets23-489?size=O%2FS&color=Waterfront+Blue to organize. The rolling duffles are very durable. I need an assist from my husband when the train has steps, otherwise I can manage it quite well. Usually runs 26-30 pounds when packed.
We also have Osprey 21” carry-ons for shorter trips and they have lasted for 7 or 8 years.
deesea206, you might consider the TravelPro Maxlite 5 International Carry-on, which is a spinner that is very lightweight (only 5.3 lbs). I have the 21-inch carry-on, and I love mine, but this one is even smaller, so you might like that. They're very durable, attractive, I think, and great bags. As I said, they're one of the lightest-weight spinners out there (about half the weight of the Away medium checked bag). It does not have the clamshell design.
I second the TravelPro brand. Bought the 21" and next size up 24" last year. Both are the lightest I have ever had. Both are spinners and not clam shell. Of course the 24" is only for checked luggage.
My current bag is this one, but it sure didn't cost me as much as this!
https://www.amazon.com/dp/B07WW1LK84?ref_=ppx_hzsearch_conn_dt_b_fed_asin_title_1&th=1
I was so used to my carry-on with 2 wheels that this bag looks enormous and somewhat ridiculous to me (wheel-wise), but it's held up well on several long trips and I have no other complaints about it.
I have an older Vaude 60l two-wheeled duffle similar to the one mentioned above that I use for trips where I have a lot of varied gear or clothing needs, and I can support the general recommendation. I find it very easy to travel with - it also stands up to rough handling on trains and under busses better than my non-clamshell rectangular suitcase of the same capacity (different use case), because it can go in at almost any angle and not roll around or fall over. I definitely find the shape makes packing cubes almost a necessity to create some sort of order, though, so not ideal for anyone who dislikes them. (My packing cubes are all super-lightweight ones from from Muji.)
Lots of responses. Did any meet your criteria?
Thanks everyone. I am now going to consider a rolling duffle- eagle creek or Patagonia--I wasn't considering those before. They do seem to be a good in-between size, larger than a carry-on but smaller than at 25" suitcase.