In lieu of track pins, I used Gargraves track connectors, GG product # 910-4, which are strips of sheet metal/steel the fit tightly between the web of the rails--no gaps or deformed rails. Simply inert and tap the rail ends to eliminate gaps. (No environmental issues in my walk-out basement layout location.
Ah! The "fit-up" connectors! Yes, I use those to close a loop or in a tight spot. The rest of the time (vast majority) I use the GarGraves track pins, including the pig-tails, and I tap them as close as possible.