I like the charcoal canister source for vacuum/boost. It is the least important device and it is one of the larger diameter sources.
Technically this source shouldn't be used for wastegates (with diaphragms) as diaphragms don't necessarily like to see vacuum. It may put extra stress and oscillations on the diaphragm that it wouldn't normally see and may shorten the life of the diaphragm. (That being said, personally I've got mine hooked up to vacuum/boost anyway.)