Given the headaches of a dry sump setup I don't think I'd do it again. The additional vacuum from the dry sump pump didn't get me any horsepower, and the additional plumbing was a nightmare. I'd go with a standard wet sump arrangement, a separate vacuum pump if I wanted crankcase vacuum, and use an accumulator, like an Accusump, to protect the engine in case the oil runs away from the pickup.
On the turbos, regardless of the oiling system I would recommend draining back to the pan. That approach is known to work. It would make me nervous to use a dry sump stage and scavenge oil directly from the turbo bearings; I'd be afraid that this approach would pull too much oil out of the bearings and lead to scuffing or worse...
