The Prestige suites are typically on the same floor as the Club Lounge (5th, I think) and have sloping ceilings due to the mansard roofing. I actually don't know why it is considered a suite of prestige, the Jr. Suites with Opera view are significantly better and grander.
Between a Prestige Suite at Le Grand and Superior room at Le Bristol -- on Virtuoso -- I would go for the Bristol.