Calling all potential visitors to the new Casa DannA (As Gaeilge: Teach DannA): should we get a day bed which converts to a full double (but is less comfy for daytime seating) or a sofa bed (which converts to a slimmed double) for the spare room?

Calling all potential visitors to the new Casa DannA (As Gaeilge: Teach DannA): would you prefer to sleep on a day bed which converts to a double bed (but isn't as comfy for daytime seating) or a sofa bed which converts to a (slightly slimmer) double bed