The 146 isn't just a bit quicker, it's a LOT quicker. Normal climb is 280kts (as opposed to 200 or so for the 328), cruise is M0.70 or thereabouts, and it is absolutely no problem to fly the 146 at 250 kts to about 8 miles or so.
Flew on a BE 146 a few months ago on the EDI-LCY sector when I was back in the UK, and wasn't surprised to see a 328 being passed so quickly it seemed to be in reverse at about 80kts!!!
The only thing better on the Dornier is the flight deck... I actually chose BE over ScotAirways as I found the BE cabin staff a lot more friendly!!
