I went with a roadie from day one and have never regretted it. I started at 252 and am currently at 195. When I started, I couldn't reach the hoods, or brakes, and breath at the same time. I'm just 5'7" so there was a ton of belly in the way. Now I can ride in the drops as much as I want too.
There's so many ways to enjoy cycling I think it depends on you. I do believe if you've got a need for speed all roads lead to a road bike. From hanging out here, I've noticed there's a majority of folks who've gone from hybrid to roadie but just a few that go from roadie to hybrid... there must be a reason.