my car wants to die at a speed around 15-20 mph?

Had this problem too and it was air getting in to the fuel pipe as the plastic pipe had perished on a joint. I would check the fuel filter for leaks, and make sure its on properly, also the connections on the vacuum hose. You probably have a load of air getting in there somewhere, and as you apply the throttle, the engine calls for more fuel, and then of course is dragging air through too. what about taking it back to the garage that just did the work? It may of course be nothing to do with the above, but it defo worth checking first.

Dan
January 2013