Any Experience with Qatar Airways and Carry On?

Hello,
Anyone hear have any experience flying with Qatar airways? I'm about to fly with them for the first time, and always try to avoid being seperated from my gear when I fly, just in case.
Their carry-on restrictions mention 21", whereas the carry-on sized pelican case is 22"". Its a small amount, but you never know how much of a stickler an airline may be. I'd hate to waste money on a different solution, but I'd hate it a lot more if there were an issue with my baggage. Its a once in a lifetime trip and I don't want to be without a camera!
Any thoughts?