That is a route I have taken twice this year so I keep an eye on the FREQUENT changes. I finally came to accept that QR will get me from ZNZ to DOH, but not necessarily at that time or on that plane and you might have a technical stop in DAR or JRO. If you have a technical stop, you will get pyjamas and probably a larger plane. Make sure to keep checking on your flight the day before and the day of travel. It could change at any time. I last flew it last month, and DOH>ZNZ was an A320 and ZNZ>DOH went out as scheduled on a 787-8.