GE47 use less current than the 44 and so give off less heat.

LED use even less current but the amount of power saved is negligable in all honesty... a couple of watts at 6v is piffle.

Coloured LED behind coloured inserts CAN look better as it gives more depth of colour, but any AC ripple can cause strobing and its very irritating.

LED in an EM???  God forbid!