Do adjustable bases work for couples with different preferences?

Yes, and a split design is the reason. With a split king or split queen, each side moves independently, so one partner can elevate their head for reading or reflux while the other stays flat, without disturbing anyone. Some models include dual remotes and separate massage settings. If you share a single non-split mattress, both sides move together, so a split configuration is the better choice when two sleepers want genuinely different positions.