Pre Covid, we sailed Seabourn and Crystal, with more sailings on Crystal. We took a spontaneous trip on Silver Moon in July as we had wanted to try Silversea.
We had a lovely stateroom, very much in line with Seabourn staterooms. Crystal cannot compare for opening price staterooms. We had good food for the most part on Silversea, but, the food did not compare to Crystal in our opinion. The service was very good, but was missing the level of warmth we found on Crystal. The included and one paid excursion were good. Enrichment and entertainment were far superior on Crystal. Other than the small Salt cocktail lounge, the others seemed empty on Silversea. We never found a good pre dinner cocktail routine.
If itinerary and relative pricing were the same, we would choose Crystal (have not sailed new Crystal), then Seabourn and third Silversea. It is certainly nice to have a larger stateroom and newer ship, but Crystal has been a wonderful total experience for us.