I own just a few full bent pipes with a condensing chamber (water well) and with an offset airway to the chamber.
I’ve deepened the water wells using the proper size drill and also opened up the airways a little, using a drill.
After a smoke or two, I take the pipe apart and keep the water well and all airways sparkling clean with Everclear, pipe cleaners, and twisted paper towels.
A full bent pipe is a wonderful thing to own, but it requires maintenance.