Here is an interesting comment that was posted on FT regarding Qsuites:
"Just got last-minute aircraft change for tomorrow's (22MAR) QR274 AMS-DOH.
I created a system (spending multiple days on it) in which I analyzed all factual cabins on this flight since the beginning on Q Suite operation in October, found out that was almost never the old cabin on Fridays, booked it for Friday, then checked my flight and all other dates every single day since the booking in January, noting the patterns of them changing the aircrafts (normally they did it one week in advance and only once they changed it on the same day), checked in online yesterday (while it was still Q Suite) only to completely get my dreams crushed today finding out it was replaced with the old cabin version. We also spent all our miles to get there in Q Suite which ended up just for nothing. Sad."