They're pretty bad about any kind of fuel pressure, they just don't have the hp behind them to pull the pintle up. In turbo territory, that's not much. That also proves to be more of a compromise than most people care to admit. So, emissions, fuel economy, idle quality, low speed drivability, etc. are all compromised, and the larger injector you get, the worse it gets. Sure they'll make tons of hp on top, but don't ask them to be nice.
Additional injectors can mean a few things.
Most of the older 930 CIS turbo owners know about adding one or two additional injectors just above the throttle body. This is a great way to increase the top end power without sacrificing any low speed performance. The controllers aren't that expensive, and the setup can add another 100hp or so. But that's CIS turbo's. We talking about serious hp here, and that takes a good digital fuel management.