Former luggage salesman.
Delsey is generally good stuff; they're kind of the European Samsonite.
Swiss Army can be good, although you want to make sure that you get Victorinox rather than Wenger, because Wenger is kind of like the American Tourister-y budget brand of Swiss Army.
Be sure to check out Travelpro; they were the ones who originally came up with the upright pullman design (the wheeled type with a handle that pretty much everyone uses these days instead of trunks), have a lot of endorsements from pilots and flight crew, and they have a lifetime warranty. Back when I was selling, they also produced some of their pieces domestically, although I don't know if that's still the case.
Get either softside luggage that uses ballistic nylon fabric or a hardside. Spinner wheels are more maneuverable, but there are some tradeoffs: you have four points of potential mechanical failure rather than two, and they are bad impact targets because they jut out from the body unlike traditional wheels.