It's comfortable, and better than the 787, which only has 2 lavatories for the entire Business Class. The 787 also has a sliding door, but I found it quite claustrophobic. The A380 feels much less so.
My recent trips on Qatar, in October, I had the same combo. Whilst the staff are very willing, the standard of F&B onboard has deteriorated, and the "a la carte" dining is chaotic. I was travelling with my partner, and we were in the middle two seats, but meal and food service did not co-ordinate, as his side was serviced by other crew. My (second) glass of champagne came after take off, his about 40 minutes later. I decided to avoid all food on the return journey, and instead ate in the lounge (in Madrid run by Iberia), and of course the Doha lounge.
The latter was packed to the gunnels on the outward journey with a long queue to get a shower, as there were a number of flights arriving at the same time.
Qatar still gets the "Airline of the Year" award, but I think that crown is no longer justified. Overall a huge disappointment after a 4 year hiatus because of covid.
Sorry. I didn't answer your question: I haven't been in a Q suite, although the 787 with the door is described as a "suite".