i have one. when i went to disassemble the setup to send my turbo out for bearing assy rebuild, the sealing ring was cracked. used hi-temp RTV to seal when i put it back together. the elbow/DP made a difference when i first installed it, response, etc, but i agree that the newer one-piece DP's look more promising, however, with the flexibility to "rotate" the DP at the elbow, might provide more clearance.
I noticed some porosity with the casting that was sealed with some kind of high-temp epoxy, it has held up well through the years.