Hey Rex,
I can imagine that you get better suction than with your previous dust boot drawing from the back. Do you still have relevant dust and chips not caught?
What dust collection system is hooked up at the end of the tubes?
I have not seen any dust shields with you so far, but you have a recess at the opening there. Do you use any? It would draw a little less external air.
I find the flexible, unbreakable shields a good idea (as shown here, here, and here)