The issue with LDS, like Tom said, is their quality has gone down hill ever since they got cutoff from S&S and their lawsuit with Bosch didn't help their public image any. Some of the big name tuners won't even tune LDS injectors as lately they take far more pressure than is reasonable. For example, I had Lauren tell me it's normal for SAC45 and SAC65 to run 7000-8000psi at idle to be clean. For comparison I have not had to run that much pressure on any other company below 250%. The 250%+ stuff can be closer to 8000-8500psi to idle clean but they also support 500-1000whp over say a SAC45% or SAC65%.
Personally I would be taking my motor to DHD as others have said. Ask yourself, can you afford to do the job twice? There is a reason DHD is so highly recommended and also arguably one of the best (if not the best) Duramax engine building shop on the globe.
12mm, 100% injectors, and a 68vgt/483 is a great setup for the 800whp area while still having great street manners. A 150% or 200% would be more ideal should your goals be closer to 1000whp. The days of a 200% being a competition only injector are gone as tuning technology and injector technology has come so darn far that they are extremely clean in all applications.