I've found the best filter to use is the Sullivan sintered cone filter that goes on the fuel line in your fuel bottle. With a bit of care it is easy to keep the fuel syringe, or whatever, clean, the ends the the fuelling lines used clean and very rarely have problems. No filters to leak or come apart on the plane, less leaky joints in the fuel line to the engine.
Another problem I had with the DuBro crap trap, especially with castor oil fuel, was it would at times collect a nearly invisible, clear gel on the finer screen that would give erratic needle settings. The engine might start lean when it was set rich, get adjusted, and then go rich during that flight or the next one.