Not sure about the vacuum drop, but if there is one significant enough to cause problems, you could simply add a vacuum reservoir to cure the problem.

I have an old Purple Shaft Hydraulic cam, 292 advertised duration, .509 lift in the 440 in my Charger. For my power brakes to work, I added a vacuum reservoir. It's just a tin can with a check valve to hold the reserve vacuum until it is needed.