Hi - I just got a 19 with a permanent bed in the front and I love it! The bed is more comfortable than the dinette cushions. But it's also more awkward to get into the storage (you have to lift up the whole mattress).
Also, they can do a couple different things for storage under the bed. I had them build it as though it was a dinette because I wanted open space under the center for a litter box.
Also, be aware that some controls (inverter, solar panel, battery disconnect, electrical outlet) are placed normally near the floor for the front dinette - so if you have a permanent bed, these controls are petty much inaccessible. Better to see if they can be moved - or just go with a dinette in front and maybe add a memory foam topper for extra cushioning.