No professional physicist I know thinks natively with relativistic mass. They much prefer m to mean the rest mass, a relativistic invariant, and to include exp

No professional physicist I know thinks natively with relativistic mass. They much prefer m to mean the rest mass, a relativistic invariant, and to include explicit factors of (v/c) or γ when they're talking about frame-dependent quantities. Anecdotally, this is also good pedagogically: the mass is an inherent, invariant property; avoiding the relativistic mass helps students. Just make sure to drive home that E^2 = (mc^2)^2 + (pc)^2 is a statement about a four-vector magnitude.