The Silverlight rendering speed depends on the common productivity of the PC (CPU, video card). More elements visible at the same time decrease productivity. If you need not to have all 2000 lines visible at the same time and you can granulate your surface to decreese the number of the visible lines, then you can try to use DynamicLayer:
I've tested RadMap with 2000 lines in it and it doesn't seems too slow actually. The speed of panning is OK, zooming is a bit slow, but not dramatically.
the Telerik team
Registration for Q1 2011 What’s New Webinar Week is now open. Mark your calendar for the week starting March 21st and book your seat
for a walk through all the exciting stuff we ship with the new release!