The BP28 BF3 proportional tube was specifically designed for the NM64 neutron monitor that was introduced to the cosmic ray community in 1964. This neutron monitor design has remained the standard to date. In 1999, during the construction phase of the Space-Ship Earth NM64 monitors, it was soon realized the cost of the highly efficient He3 filled proportional tubes, manufactured by the LND company, were less than a BP28, and provided nearly the same sensitivity as a BP28 in a NM64 structure. Consequently, the LND He3 tubes were chosen for the new SSE NM64 stations, to upgrade stations Thule, South Pole and Newark. Unfortunately, since then, the price of the He3 tubes has significantly increased, due to the rising cost of He3, and the original BP28 tubes are no longer manufactured. Consequently, we have embarked on an investigation to evaluate a suitable BF3 proportional tube to replace the original BP28. The investigation will include characterization of key performance parameters of two slightly different proportional tubes, with different anode wire and cathode tube thicknesses, while maintaining the same tube geometry, gas volume, pressure and purity. In this paper we will present measurements and discuss the results