Pros and cons of engines under floorboards

[crashkahuna]

Looking at some vintage boats. What do you think of design where engine is basically in the bilge? My initial thought is not good but maybe some advantage like shorter, more horizontal prop shaft. What say those of you that have owned these?

[model 10]

Dirt is the only complaint I have. Access to the engine and trans is really great but in our boat, debris work their way through the cracks and end up on top of the engine etc.