Last time I voluntarily checked a bag was at least 15 years ago (had to check luggage when flying was part of work as I needed tools like screwdrivers).

On my first almost three week trip to Southeast Asia I had a soft sided carryon/backpack that I bought at a garage sale and loved dearly. Sadly, it didn't survive Hurricane Ike (IIRC, the big one that got Galveston). And yes, at that point it was held together with a little duct tape

I've traveled for the longest time with a couple of backpacks - one smaller than official rules and the other smaller than persona item, though being *A Gold does help. Now the larger one is a rollaboard, but it still has the straps like a backpack, so I can use it in that fashion if I had to - rollaboards don't do well with European cobblestones

Now that I think about it, it's kind of funny in that I don't want to waste time waiting for luggage, but will go out of my way for extra miles. Well, used to ... now that UA no longer gives you the miles flown, it loses the point

Don't forget, you can get pretty much everything in Europe that you can get here. Haven't been to Poland, but imagine it can't be that much different from Czech Republic or Slovakia.