White dwarfs wouldn't make good distance indicators because they explode often? Does this seem true?

Answer 1

No. They don't make good distance indicators, but that's not the reason.

White dwarfs are the stable end stage of stars like our sun. They have stopped fusing any material, and are kept from collapsing further by the repulsion of tightly-packed electrons. The only way one will explode, is if it accretes material from a companion, raising its mass to an unstable point, and destroying itself in a Type 1A supernova. An isolated white dwarf will never do this.

They make bad distance indicators because they come in a fairly wide range of masses and inherent brightnesses.

Oh, and - they're also not particularly luminous, which makes them difficult to measure accurately.