As far as I know, the boats have the same interior dimensions. I have a 25SE and briefly climbed on the 25DV - they seemed to be the same. The SE pounds a bit, but this can be mitigated by slowing down and using your tabs. I don't think one will necessarily be wetter, but the DV's ride will be smoother when it gets choppy.
300hp seems to adequately power the SE. With a single 300, I get get 2.8-3mpg at cruise, and top out around 47mph with a fairly light load. The DV with twin 150s from the performance bulletin never breaks 2mpg. I spend 80% of my time inshore/nearshore, and wanted a single engine. In my opinion the DV is a bit underpowered with 300hp, and really shines with the twin 200hp setup. Truth be told, if I could have got a 25DV with a single 350hp, I would have taken it in a heartbeat. Unfortunately, most Parker dealers seem to be less than accommodating with special requests, or really with anything else for that matter. In the end the SE fit nearly all of my needs, and I am very happy with the boat.