you are not going to want solid for a street driven car. The vibration are going to piss you off so bad. Poly mounts will do just fine with little/no vibration increase.
I don't think solids are a problem. I was surprised at how little vibration is actually transferred into the car compared to what I had heard. Mostly you feel it in the steering wheel.
I use solid's on the street and it's not a problem. the car shakes yes, but its a cammed V8, why woyuldnt it. The key is to keep the rubber trans mount. If u use urethane motor and tranny mounts, u will rettle ur teeth out, or solid motor and urethane tranny u will also rattle ur teeth out. Later