I think the system hierarchy approach might help reduce the number of comparisons needed here.
If I had a 272, was considering an upgrade, and my local Naim dealer wasn’t too busy to do comparative demonstrations with equipment that I own, I would ask to do this sequence of comparisons
- 272 vs 222 into 250 DR
- Naked winning preamp v naked winning preamp+300NPX into 250 DR (say, 222 vs 222+300NPX into 250 DR)
- Winning preamp+PSU into 250 DR v 250 NC (say, 222+300NPX into 250 DR vs 250 NC)