Have a look on frequent flyer forums, cabin crew websites, etc - a quick Google will bring up some, but F
lyertalk is a start, as is Pprune
http://www.pprune.org/archive/index.php/t-219518.html. Thats useful because cabin crew etc have to do it as a job, so their luggage has to be sturdy, practical, and fit the space available.
I had to do some research for my wife when she started flying longhaul for work (mainly travel blankets, but luggage as well), and there is loads of information out there. This gives a top ten
https://gearpatrol.com/2015/04/06/best-carry-on-luggage/ and there are a load of similar lists on the net.
Samsonite and Delsey are popular, (and Tumi gets mentioned a lot as well) but if you going to the US, or you can score on Ebay or Amazon, you get brands like Luggageworks
http://www.luggageworks.com/ (they do their own, as well as others), and they also stock Travelpro, which seems very highly rated. A US brand, they do have a UK website
http://www.travelpro.co.uk/, and they are on Amazon. Not cheap, but buy cheap buy twice.
London Luggage does Travelpro, Samsonite, etc
https://www.londonluggage.co.uk/collections/sale/samsonite . They also do Rimowa, which is just eye wateringly expensive (they also make cases for certain airlines 1st class passenger amenity kits - have a look on ebay for just how much an empty case will go for!).
My wife got a Samsonite rolling tote really cheap in a shop in Boston last year, so there are bargains to be had.
Alas, I have zero need of nice luggage, but I can dream!