I might be getting old (39) but solid for a DD is a bit much. It will be up to you and what you can handle with all the NVH (noise, vibration, harshness). Solid motor mounts will be transmitting everything the motor is doing like shaking more sound.
1989 Sonic Blue Mustang LX Coupe, 349 ci, TW heads, TFS Track Heat intake, 75mm Accufab TB, 80mm ProM, 30 lb inj., Jay Allen cam, TKO, 3.73, 31 spline w/ TruTrac, MAC 1-5/8" LT headers w/ h-pipe, 2-1/2 flowmaster, electric fan oh and a Moates QH
392 rwhp 424 rwtq....Mustang Dyno
"There are three kinds of men. The one that learns by reading. The few who learn by observation. The rest of them have to pee on the electric fence for themselves." -Will Rogers-